PinoyDVD: The Pinoy Digital Video & Devices Community
Home Theater => Audio => Tubes => Topic started by: alexg on Mar 26, 2007 at 04:04 PM
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Update 03 November 2007:
Almost done drilling and cutting the alum top plate of my new tube amplifier:
(http://farm3.static.flickr.com/2160/1839726471_6a78ec1b40_o.jpg)
When done, it will produce a GLORIOUS (hold your breath), 1.0 (ONE) watt of power per channel, hehehehe.....
It is a parafeed circuit, 12b4 tube providing the power and either a 5670 or 6n1p driver. It will be tube rectified using 6X5 rectifier and no electrolytic on the PSU!
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Just finished this KT88 SE amp based on Mikael's design (diyaudio), with modifications done by arnoldc.
The power transformer and OPT was wound by Edrel Sison, the choke was a Hammond 193J. The driver is a Sovtek 6n1p and the power tubes are 6550/KT88. Rectifier is a 5u4-gb. It put out around 12 watts per channel.
The hefty power transformer:
(http://farm2.static.flickr.com/1330/1360822692_c5b1947fb1_o.jpg)
My preliminary layout:
(http://farm2.static.flickr.com/1312/1360739320_9f785b5928_o.jpg)
The aluminum top plate with all the holes done and the narra plinth assembled:
(http://farm2.static.flickr.com/1278/1359933875_724de0b527_o.jpg)
With all the topside component installed (not wired yet):
(http://farm2.static.flickr.com/1193/1359933337_7458e8a33e_o.jpg)
Finished the wiring last week and when I powered it up it did not smoke nor explode! ;D The fun part is, it plays music. Great sound, even better than my commercial KT88 push pull amp. I also finished oiling the narra plinth (used tung oil for varnish). Will take better pictures next time and post it here.
Thanks to ArnoldC, s2kov, Edrel, and Tony for the patience, advise and technical answers to all my newbie tech questions!
I had so much fun doing the amp, that I just started a preamp project. The PSU of this preamp project will be tube rectified and tube regulated, using plate chokes instead of plate resistors for load. As I type this, the power supply transformer and choke is being wound.
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congrats alex! ;D
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congrats! :D
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Congrats Alex! where did you buy the parts?
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Congrats Alex!
Tung oil finished diy narra plinth base,clear coated machine buffed aluminum base?...etc
Tube rolling naman cguro kasunod nyan? :D
Tsaka, a nice horny preamp to match it with?.....
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CONGRATS!
sarap makinig ng pasyon dyan nex wk!!! ;D ;D ;D
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Congrats Alex! where did you buy the parts?
The KT88 and 6550 tubes, I already have, spare for my KT88 push pull amp. The 6n1p tube and the Hammond choke I bought from ArnoldC. The power transformer and output transformer, Edrel Sison of Fetronic, wind for me, also got some teflon wires and capacitor from him.
The resistors and electrolytic caps I got from RS online, the PIO motor run capacitors I got from my office, the IEC plug salvaged from a PC PSU. The switches are also salvaged from different sources. The 1.5mm OFC solid wire used for the ground bus, I got from Ace Hardware. The aluminum chassis, I bought from Binondo (along T. Alonso St.). Other odds and ends, got from Deeco.
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Congrats Alex!
Tung oil finished diy narra plinth base,clear coated machine buffed aluminum base?...etc
Tube rolling naman cguro kasunod nyan? :D
Tsaka, a nice horny preamp to match it with?.....
Parts for the horny preamp is almost complete, Edrel will be finished winding the irons tomorrow (unfortunately I can't go to Rosario to pick it up, until next week).
Picked up the aluminum plate, aluminum rod and angle bar today from Binondo, also got the rectifier and regulator tubes from our friendly "tube magnate."
How about your "horny" project, how is it going?
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CONGRATS!
sarap makinig ng pasyon dyan nex wk!!! ;D ;D ;D
Hehehehe.... With a pair of Svet 6550C, the vocals are quite excellent! Must be good for pasyon...
Thanks.
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Hehehehe.... With a pair of Svet 6550C, the vocals are quite excellent! Must be good for pasyon...
Thanks.
para di ka ma-ear-fatigue sa pabasa, try sub mo 6n1p ng amperex 6dj8 - yung A-Frame or L-bracket or dimpled getter ;D
tol swerte ni brod, napamanahan mo agad ng tube amp ah! ;D
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tol swerte ni brod, napamanahan mo agad ng tube amp ah! ;D
Actually hindi naman pamana, I just gave him an offer he cannot refuse. ;D Gives pa! ;)
As soon as I go to Diliman, I can try a 6dj8. :)
I FORGOT THAT I WAS USING MY WIFE'S LAPTOP AND SHE WAS LOGGED IN, SORRY -- ALEXG
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Actually hindi naman pamana, I just gave him an offer he cannot refuse. ;D Gives pa! ;)
As soon as I go to Diliman, I can try a 6dj8. :)
I FORGOT THAT I WAS USING MY WIFE'S LAPTOP AND SHE WAS LOGGED IN, SORRY -- ALEXG
shades of marlon brando aka don vito corleone ;D
pero yung "Gives pa!" ang matindi ;D
coordinate mo baka pabakasyon naman sa LB yung mama.
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Congratulations!
your chassis maker also made the wooden panels? Thanks!
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Congratulations!
your chassis maker also made the wooden panels? Thanks!
Thanks.
I did all the chassis work (metal and wood) including the automotive clearcoat of the aluminum plate and the tung oil varnish on the wood plinth. It was fun doing all of it.
I just started a new project, a preamp will post pictures of it too.
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power transformer
(http://i175.photobucket.com/albums/w155/edrelsison_2007/PTX.jpg)
plate chokes
(http://i175.photobucket.com/albums/w155/edrelsison_2007/Chokes.jpg)
enjoy! :)
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power transformer
(http://i175.photobucket.com/albums/w155/edrelsison_2007/PTX.jpg)
plate chokes
(http://i175.photobucket.com/albums/w155/edrelsison_2007/Chokes.jpg)
enjoy! :)
Edrel,
Thanks for winding these babies!
Time to be "HORNY"... hehehehe.... ;D
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a nice chrome finish would be pretty for that 2 plate chokes. c'mon post that very nice preamp chassis of yours!
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edrel,
ako na kaya magpost para kay alex! ;D
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sige nga andy, simulan mo!
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This is the external PSU of my "Horny Preamp Project."
(http://farm2.static.flickr.com/1406/1360825462_9b055394fc_o.jpg)
The PSU has a power transformer with 180-0-180 80ma, 6.3V 2A, 6.3V 2A and 5V 0.8A taps, and a smoothing choke and uses motor run capacitors. The HV will be rectified using a Raytheon 6X5 rectifier and the filament using bridge diodes. Am utilizing a 4 conductor locking connector and will use a 3 foot umbilical cord going to the preamp chasis.
At the preamp chassis, the HV will be regulated using an 0d3 VR to 150VDC. Plate will be choke loaded and cathode biased using LEDs (will take pictures as soon as I started construction of the preamp chasis).
The design of this preamp was originally done by Gary (http://www.the-planet.org/linestage.html), first done locally by Edrel Sison with modification from TonyT (plate choke, etc). I borrowed Edrel's preamp and I was totally impressed by it.
Some valuable advise was given to me by ArnoldC (external PSU and LED bias) and TonyT on the (external PSU and plate choke).
All my irons were wound and designed by Edrel Sison of Fetronic, EPZA, Rosario Cavite. He also provided me with other components for the projects. The irons he did for my KT88 project are excellent, the ptx is barely warm to the touch and the OPTs sounds great!
Thanks to these guys for their advice. Thanks to Gerry, Dana and s2kov too!
By the way, this external PSU can also power a 12b4 with plate chokes and a foreplay 3. So depending on my mood, I can have the sweet sounding 7193, or a very neutral 12b4 or a classic 12au7 sounding preamp (foreplay 3).
These preamp should be joining my KT88 soon!
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This is the external PSU of my "Horny Preamp Project."
(http://www.filehigh.com/serve/19211/383486.jpg)
congrats again alexg! sakto sa easter yan.
sure smooth sounding ang horny preamp mo, alagang jergens! ;D
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congrats again alexg! sakto sa easter yan.
sure smooth sounding ang horny preamp mo, alagang jergens! ;D
Oooopppps, nabisto ang secret ingredient ko. ;D
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woohoo! :o cograts alex! ;D
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ayuz na ayuz yan, ah! chassis pa lang, ulam na...
congrats on another masterpiece in the making.... ;D
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Oooopppps, nabisto ang secret ingredient ko. ;D
Good job alexg, ;D we have to let the cat out of the bag....edrel do make fine transformers, pang export ang quality, now we have a go to person for transfomers.. ;D just as we have gerry to go to for tubes... ;D
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The back "mini-skirt" of the PSU with all the electrical connections finished:
(http://farm2.static.flickr.com/1436/1360825928_92d2d63ab6_o.jpg)
Next will be sanding the aluminum plates and legs and the narra skirts.
I am just waiting for my socket hole drill bit, arriving tomorrow pm from Singapore, courtesy of my brother-in-law.
After drilling the socket hole, then I will apply polyurethane automotive clear coat, bake it and then soldering time!
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(http://farm2.static.flickr.com/1108/1360826820_70d9474c95_o.jpg)
(http://farm2.static.flickr.com/1136/1360826378_ffacbbabcc_o.jpg)
Just finished fitting the chassis for the preamp and doing possible tube layout.
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:o :o :o nice legs! iba tlaga pag kompletos rekados ultimo sahog siguro primera klase = mouthwatering fingerlickin good! CONGRATS!
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:o :o :o nice legs! iba tlaga pag kompletos rekados ultimo sahog siguro primera klase = mouthwatering fingerlickin good! CONGRATS!
Thanks.
Those legs are not as good looking as the UP campus figures' legs during our time. ;D
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alexg,
if you are mounting the chokes underneath the chasiss, make them at right angle with each other to minimize interaction, if atop the chassis, get them as far away as possible...
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alexg,
if you are mounting the chokes underneath the chasiss, make them at right angle with each other to minimize interaction, if atop the chassis, get them as far away as possible...
Thanks for the advise.
I am still deciding if I will mount the plate choke top side or underneath. Most likely on the top and have the end bells and bracket chromed. 8)
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Hi Alex,
Gwafo ah! ;D
Tlga ba'ng sa preamp chassis naka mount yung od3?
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Hi Alex,
Gwafo ah! ;D
Tlga ba'ng sa preamp chassis naka mount yung od3?
crowded na dun sa PSU ;D
and besides, the purple glow looks good with the "hornies" 8)
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Thanks.
Those legs are not as good looking as the UP campus figures' legs during our time. ;D
uh-huh?... ::) recalling them bimbos again, are ya?? ;D
christineG
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uh-huh?... ::) recalling them bimbos again, are ya?? ;D
christineG
Oooooppppps forgot that my wife is a member of the forum. There goes my audio budget! ;D
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(http://farm2.static.flickr.com/1376/1359944569_c37bcfc046_o.jpg)
(http://farm2.static.flickr.com/1168/1360831488_ad3de46034_o.jpg)
(http://farm2.static.flickr.com/1375/1359939345_9ef8938010_o.jpg)
I was short of 1 pair RCA when I decided to put a simple toggle input selector switch.
The plate choke will be chromed.
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congrats alex! :D
PS: pssst, baka may spare kang 6922? :D :D :D
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congrats alex! :D
PS: pssst, baka may spare kang 6922? :D :D :D
Sorry, wala eh. 6922 is a reduced heater current version of the 6dj8?
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uy, ala peter daniels yan ah... ;D
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Hi alex,
Since the you're using aluminum chassis, i suggest using powder coat in wrinkle finish on your plate chokes! :)
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Hi alex,
Since the you're using aluminum chassis, i suggest using powder coat in wrinkle finish on your plate chokes! :)
I had wrinkle finished line stage, hirap tanggalin ang dust. Baka pa-paint ko na lang sa office ko, flat black.
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Finished clear coating the top aluminum plate yesterday afternoon.
I spent most of last night and today soldering the components.
First time I turned it on, the right channel is quite distorted, after re-soldering some questionable solder, distortion is gone.
But the sound was still veiled, took another look at the circuit, found out I made a mistake in installing the bleeder resistor, the resistance is quite low, it was eating all my current. Replaced the resistor, and wow!!!
Here is the pix of the preamp without the skirts yet. Visible are the LEDs I used for biasing the cathode.
(http://farm2.static.flickr.com/1105/1360837050_832ddf2e9a_o.jpg)
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alexg,
are those plate caps from zhiang? ;D
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alexg,
are those plate caps from zhiang? ;D
Got them from Edrel, and I believe he ordered them from China, might be the same source.
BTW, am using Philips polypropylene signal capacitors, and they sound good!
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pre sent u PM
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Sent you reply to your pm.
All my irons are wound by Edrel Sison (he has a tranny factory sa EPZA, Rosario, Cavite). He uses high-quality core meant for audio on all his transformers and and all are wound very accurately, am getting voltages that I specified. He is also deep into the audio hobby (tubes) that he has very good understanding of tube audio and can relate this to his transformers.
Try his irons, you would not regret it!
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thanks to your input
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para di ka ma-ear-fatigue sa pabasa, try sub mo 6n1p ng amperex 6dj8 - yung A-Frame or L-bracket or dimpled getter ;D
tol swerte ni brod, napamanahan mo agad ng tube amp ah! ;D
After trying the 6dj8 in place of the 6n1p, the vocals are ok, but for higher volume the sound is quite compressed and distorted.
I checked my circuit and 6dj8 operating points, my circuit has a very high B+ and I don't think 6dj8 is a 6n1p equivalent on circuits with high B+ (400VDC), it might do well if I reduce the plate voltage, so I would stick with the 6n1p.
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As Dana says on his 7193 preamp thread, "This year is the year of the horns."
(http://www.filehigh.com/serve/19211/385446.jpg)
(http://www.filehigh.com/serve/19211/387307.jpg)
My 7193 preamp.
(http://www.filehigh.com/serve/19211/415160.jpg)
The 832 PP amp that I will be building soon.
(http://www.filehigh.com/serve/19211/415159.jpg)
Close up
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anakngteteng...only in my dreams 832!!!
puro horns nasaan ang buntoooot??? ;D
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anakngteteng...only in my dreams 832!!!
puro horns nasaan ang buntoooot??? ;D
These tubes are quite inexpensive, contact your favorite tube magnate and friendly tube pusher.
These amps, if parts are chosen carefully can be built for less than 15K, if you can be satisfied with 4 watts of undistorted power per channel operating push pull.
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Can the supply of these tubes be counted by the hands and feet or are these free flowing?
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Can the supply of these tubes be counted by the hands and feet or are these free flowing?
Not free flowing, but enough to build a few dozen amps.
On the other hand, it is readily available from internet dealers. As far as we know, only a couple of schematic is available on the internet, so these tubes are not that popular, unlike the likes of the 6l6, el84, el34, etc.
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congrats alex...if you're building one again, please let me know...any chance with a phonostage?? :D :D :D
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congrats alex...if you're building one again, please let me know...any chance with a phonostage?? :D :D :D
I would love to do a phonostage, unfortunately, I don't have any LPs and I just sold my turntable, so I cannot test it.
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(http://i175.photobucket.com/albums/w155/edrelsison_2007/VT287.jpg)
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(http://i175.photobucket.com/albums/w155/edrelsison_2007/VT287.jpg)
What kind of tube is this?
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what tube is that,much bigger physically than the 832s?
Horny Alexg, maganda yang plano mo regarding the forthcoming 832 build plans.im sure,dami rin interested jan...
Maganda cguro, purist horny set-up:
Horny 7193 pre-amp
Horny Power Tube Amp (832s ba?)
Folded Horn Speaker System Design (Fostex driver)
You're getting good at it and getting very prolific pa, im sure nagiging istorbo na trabaho mo sa hobby natin :D...pati speaker building, pinasok mo na rin pala (fostex, folded horn combination, did i hear it right?) :).
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Carpentry is a hobby of mine too, in fact, kaya di matapos yung master bedroom ng house ko kasi kami nung wife ko ang gumagawa. ;D
I started building speaker enclosures for my car audio, mostly subwoofers. Up to the point that I start making customized subwoofer enclosures made of fiberglass for my friends.
The last speaker project I did is: http://diyaudioprojects.com/Speakers/FE127E_SB_ag/FE127E_SB_ag.htm
After I finish putting narra parquet on my folded horns, I will post pixtures.
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Its an 815 (VT287). I will try to make a pp amp out of it. It has an octal base.
http://www.nj7p.org/Tube4.php?tube=815
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3B28 half wave rectifier. i have two of these so that i can make a FW outboard PSU for big amps.
(http://i175.photobucket.com/albums/w155/edrelsison_2007/3B28.jpg)
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Nice sweet work of art, alexg. Congrat!
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Just finished gluing and sanding the narra parquet strips on my inverted BIB with karlson slot (from diyaudio.com, a folded horn). This speaker uses the 4.5" Fostex 127e fullrange driver.
You would not believe the bass am getting from this 4.5" driver, bass is a bit better than my Evo 10, and the vocals and highs are to die for. Here is a picture of the un-varnished cabinet:
(http://www.filehigh.com/serve/19211/419789.jpg)
On the right on my audio rack, my diy KT88/EL34 SE amp, my 7193 "horny" preamp, the preamp PSU below, not shown is my Monica2 DAC (from diyparadise.com) and my 6688 line stage for the DAC. Also not shown is my very old Philips DVD player that I use to play CD and my 250GB MediaGate audio and movie player.
The folded horn speakers will be stained cherry and finished either with Tung Oil or Polyurethane satin finish.
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Congrats, Alexg! Set up shown is best for "show". I don't see the Pi-10. Have you tested it.
I have invited Edrel to organize the DIY group for the July 6, 7 and 8 in Alabang.
cyber
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Congrats, Alexg! Set up shown is best for "show". I don't see the Pi-10. Have you tested it.
I have invited Edrel to organize the DIY group for the July 6, 7 and 8 in Alabang.
cyber
The Pi-10 is for HT and for my SS amp.
It sounds great, thanks.
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Very nice work, Alexg!
Mukhang wala munang upgrade for the longest time... :)
Halos complete DIY set-up na yan...
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I started breadboarding my 832A PP monoblocks.
I started with 6n1p as drivers using only one triode and now am using a paralleled 12au7.
The phase inverter is a transformer (not an interstage). If I was doing a stereo, then it would be possible to do a 3 tube push pull amp.
With the transformer phase inverter, the sound is very, very good! I just needed to deal with the hum (might be due to having an MDF board for a chassis). This amp has very, very good potential, it sounds better than my SE KT88!
Here are the pictures of the breadboarded amp:
(http://www.filehigh.com/serve/19211/449720.jpg)
(http://www.filehigh.com/serve/19211/449721.jpg)
The PSU is SS rectified and is CLCRC filtered, using electrolytic caps... (in contrast with my KT88 that I used motor run caps). The driver is plate choke loaded and currently biased using red LEDs which I plan to replace with an LM317 bias and later on a CCS based on the diyaudio CCS. The 832A will be biased using LM317s.
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WOW :o...Horny all the way :o
Am sure, it will turn out good just like the previous ones you just made.
Next update please ;D....
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WOW :o...Horny all the way :o
Am sure, it will turn out good just like the previous ones you just made.
Next update please ;D....
OT: Dana, are you going to the Alabang Audio Show?
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With the transformer phase inverter, the sound is very, very good! I just needed to deal with the hum (might be due to having an MDF board for a chassis). This amp has very, very good potential, it sounds better than my SE KT88!
hum should all but dissappear once you finalize lay-out on chassis...congrats, we proved the skeptics wrong! ......we can do it!!!! ;D ;D ;D
tube amps are really about irons....and solid state biasing a bonus...
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hum should all but dissappear once you finalize lay-out on chassis...congrats, we proved the skeptics wrong! ......we can do it!!!! ;D ;D ;D
tube amps are really about irons....and solid state biasing a bonus...
I was reading the thread on the Seth Amp on diyaudio, and a lot of forum members were convinced that it will not work (frequency response problems, etc, etc), though the circuit designer was saying that it sounds very, very good.
Yes, Tony, we have proved the skeptics wrong! It can be done, and it does not need to cost an arm and a leg, (maybe it would cost just a couple of fingers though ;D).
Thanks for the winding design!
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OT: Dana, are you going to the Alabang Audio Show?
still not sure...having beta sample run on new projects, with visitors >:(.
will try hard to be there...see/listen to our toy too and get d horny feeling... ;D
832s.....hmmmmmmmmmmmmmm
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Assembled one monoblock on the unfinished aluminum chassis just to dry fit and position all the holes that needed to be drilled:
(http://www.filehigh.com/serve/19211/451661.jpg)
(http://www.filehigh.com/serve/19211/451662.jpg)
(http://www.filehigh.com/serve/19211/451663.jpg)
Now I am playing the system in stereo, excellent sound, excellent soundstage, minor hum issue (need further tweaking), bass is a bit flabby and the highs a bit too edgy, adjustments should fix this.
This amp have a lot of potential!
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hum should all but dissappear once you finalize lay-out on chassis...congrats, we proved the skeptics wrong! ......we can do it!!!! ;D ;D ;D
tube amps are really about irons....and solid state biasing a bonus...
Tony,
I took out the center tapped choke phase inverter and used a technique I read at Yeo's website (diyparadise.com) on his Simple EL84 PP amp. (driver tube plate to grid of one power tube, the grid of the other power tube to ground).
Promising too, more natural sound, a bit attenuated overall, but good. But of course, I really love the heft and weight of irons on a tube amp. ;D
BTW, hum is still present on my prototype on the final chassis, I will try using shielded cables for signal cable, if I can't get rid of the hum, then I will rectify heater supply.
Regards,
Alex
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Latest picture of my 832 monoblocks:
(http://www.filehigh.com/serve/19211/454712.jpg)
The one on the right is the latest, the other one with the 6j5 mounted horizontally has the chassis drilled for a 9 pin driver that I was using before (6n1p and 12au7). I have to used a short piece of aluminum angle bar to mount the octal based 6j5.
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My new project, a pair of 832A monoblock amp. Here are the pictures:
(http://farm2.static.flickr.com/1313/1359948717_d9f3c4c42d_o.jpg)
(http://farm2.static.flickr.com/1235/1360838926_91e7e9da9e_o.jpg)
Breadboarded.
I started using a 6n1p as driver, sounds good but too much gain. Tried 12au7, same thing, bass is more prominent. Finally settled with 6j5 for driver.
I used a transformer for phase inverter, sounds good and better than an LTP. Edrel Sison wound all the irons, and as usual, they sound great. But now, I settled with a self-inverting topology.
Here is the upskirt shot of the first prototype.
(http://farm2.static.flickr.com/1026/1359950637_943cf15dcf_o.jpg)
With the 12au7 driver:
(http://farm2.static.flickr.com/1398/1360840788_faca32f0b9_o.jpg)
Finally, with the 6j5 drivers.
(http://farm2.static.flickr.com/1166/1360841416_e2000ecc57_o.jpg)
The monoblock on the left still have the driver tube mounted on an alum angle bar (this allows me to experiment with different size driver tube sockets (nine pin and octal). The one on the right will be the final chassis with the 6j5 driver.
I just needed to sand and paint the chassis and it's done, except for some minor tweaks.
The sound: It sounds better than my SE KT88 that was at the last Alabang Show (the one paired with the Vandersteen 1C).
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sir alexg, pwedeng humingi ng circuit diagram ng pre and power tube amp? :)
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sir alexg, pwedeng humingi ng circuit diagram ng pre and power tube amp? :)
pm me your email and i will send you the schematics..
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sir alexg, pwedeng humingi ng circuit diagram ng pre and power tube amp? :)
Tony can email you the schematic nung preamp, he is instrumental in the design of this preamp.
Which power amp do you need the schematic, the KT88 or the 832A?
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Tony can email you the schematic nung preamp, he is instrumental in the design of this preamp.
Which power amp do you need the schematic, the KT88 or the 832A?
S' Alex/ Tony,
If you don't mind, pasend din sa email nang schematics. WOW na WOW ako last audio fair sa DIY room niyo. Will send you PM, thanks!
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for a first time diy, this should be okey, not complicated ang circuit, simple lang...tubes are available from Gerry, and chokes are available from edrel...
those who wish to build these horny amps, just fire me pm with your email.... ;D
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pm me your email and i will send you the schematics..
sir TonyT, thanky you very much.
Tony can email you the schematic nung preamp, he is instrumental in the design of this preamp.
Which power amp do you need the schematic, the KT88 or the 832A?
sir alexg, alin po sa dalawa ang maganda ang tunog? okay lang ba kung parehas ko hingin?
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you can start here:http://www.diyaudio.com/forums/showthread.php?s=&threadid=102510 (http://www.diyaudio.com/forums/showthread.php?s=&threadid=102510)
832, 829, 815 are dual pentodes, they are not hard to drive judging from datasheets, one caveat though is low screen voltage rating, but this is not much of an issue imho. ;D
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sir TonyT, thanky you very much.
sir alexg, alin po sa dalawa ang maganda ang tunog? okay lang ba kung parehas ko hingin?
Go with the 832A, study this circuit: http://audiohobbyist.com/projects/832.htm
When you are ready to do your amp, PM me and I will tell you how I modified and tweaked the amp. My apology, I have not drawn the diagram of my 832A amp yet.
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maraming salamat po mga sir.
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(http://farm2.static.flickr.com/1376/1359944569_c37bcfc046_o.jpg)
(http://farm2.static.flickr.com/1168/1360831488_ad3de46034_o.jpg)
(http://farm2.static.flickr.com/1375/1359939345_9ef8938010_o.jpg)
I was short of 1 pair RCA when I decided to put a simple toggle input selector switch.
The plate choke will be chromed.
This preamp have been done with several tubes now, on the original version, I used 7193 (half of 6sn7), then later, I used 6j5 (another version of a half of 6sn7), currently it has 12b4 tubes on it.
picture of the preamp with GE 12b4:
(http://farm2.static.flickr.com/1083/1359953001_b095e4c453_o.jpg)
Tonight, am wiring it with 12au7 on a cathode follower, similar to the Foreplay III.
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pm me your email and i will send you the schematics..
hi sir TonyT, interested din ako sa schematic diagram, gusto ko subukan maggawa ng sarili ko tube amp, hope you can give kahit yung pinaka-simple lang na diagram, first time ko lang po ito gawin, kaya pwede ring may instrauctions ng pag-gawa, parang for dummies ang dating, hehehe :)
btw, here's my email address.... [email protected]
TIA ;)
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Finally, I had some spare time and started building my cathode follower 12ua7 preamp (Foreplay 3 inspired).
(http://farm2.static.flickr.com/1006/1414313837_3c34521e35_o.jpg)
Trial layout of the components. No cheap surplus PC PSU capacitors were used, Nichicon electrolytics and ASC polypropylene in oil (also known as motor run) were used. Unlike the stock Foreplay 3, I used chokes on the PSU which sounds better than an RC filter for this linestage.
(http://farm2.static.flickr.com/1167/1414314309_f19d051c57_o.jpg)
Assembly finished, tweaking still going on. The nice coke bottle tube behind the 12au7 is an 0D3 voltage regulator. Tweaks include CCS plate load and CCS cathode bias, well filtered SS rectified PSU using mostly polypropylene capacitors. Sound is quite excellent.
(http://farm2.static.flickr.com/1029/1415194672_aa57ebe46e_o.jpg)
Preamp at night!
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naks! tapos na pala! ;D
congrats! :)
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naks! tapos na pala! ;D
congrats! :)
Thanks Andy. This preamp really sounds good with my SE KT88 and my 832A PP amp.
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Looks really nice, Sir alexg, and I guess sounds good as well :D
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Looks really nice, Sir alexg, and I guess sounds good as well :D
Romy,
It does sound excellent. The design is very popular and has received great reviews.
What I did was revise the PSU circuit. The cost of this preamp is really, really inexpensive compared to similar sounding preamp.
Regards,
Alex
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Hi Alexg...its been awhile since I've been to this thread...
Ang dami na palang creations...hehehe...pede na mag showroom.
Ganda ng pagkagawa...mula sa chassis.First, was the all aluminum chassis and lately, the wood/aluminum combi...very nice.
Last time, i understand u threw away some of the 12au7s after creating the horny preamps :D
Wala yata tlagang matatawag na 'tapon' na tubes...
Again, congrats for the energy and passion!...kkainggit...
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Hi Alexg...its been awhile since I've been to this thread...
Ang dami na palang creations...hehehe...pede na mag showroom.
Ganda ng pagkagawa...mula sa chassis.First, was the all aluminum chassis and lately, the wood/aluminum combi...very nice.
Last time, i understand u threw away some of the 12au7s after creating the horny preamps :D
Wala yata tlagang matatawag na 'tapon' na tubes...
Again, congrats for the energy and passion!...kkainggit...
Don,
I was trying to stay away from the foreplay circuit as I know the 12au7 has the reputation of adding too much color on the sound.
But our friend, the winder, convinced me to try and since I have an external PSU supplying 150VDC which is how the foreplay is made, I tried using some of my 12au7 that I have no need for.
The sound is great with my SE KT88, not neutral, but I liked what I hear. I did have to tweak the PSU and try different output caps (most output caps, like Wima, etc. will give the circuit a really colored sound) and experimented with different cathode bias (LED, LM317, CCS). I somehow arrive at a sound that is airy, not too sibilant and tighter bass. It is just a combination of PSU caps, CCS and output caps that will give you the least colored sound.
I have tried the preamp on tube amp (832 and KT88 SE) and SS amp (Rotel), with great result.
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Let the new project begin.....
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Let the new project begin.....
Sir Edrel, hmmm.... ;)
Congrats Sir Alex and congrats to me, hehe.. :o
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Sir Edrel, hmmm.... ;)
Congrats Sir Alex and congrats to me, hehe.. :o
Hehehe... how is the sound so far?
I just tweaked my 832A amp, and have installed a 5670 driver, somehow the sound is more balanced (as far as the bass and highs are concerned) than the 6j5 driver. I will be trying different load lines for the 5670 and see how it sounds, so far with a cathode bias of 1.5V, am getting great results.
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Hehehe... how is the sound so far?
I just tweaked my 832A amp, and have installed a 5670 driver, somehow the sound is more balanced (as far as the bass and highs are concerned) than the 6j5 driver. I will be trying different load lines for the 5670 and see how it sounds, so far with a cathode bias of 1.5V, am getting great results.
As I have said sir, the bass got tighter after 3 straight days of listening (hopefully my boss is not a member of this forum). Parang kumakaway na tuloy yung bahista ni diana krall sakin, hehehe. ;D
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As I have said sir, the bass got tighter after 3 straight days of listening (hopefully my boss is not a member of this forum). Parang kumakaway na tuloy yung bahista ni diana krall sakin, hehehe. ;D
Most people who used the Mundorf output caps that I used say that you really need to burn in those caps.
Enjoy!
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Most people who used the Mundorf output caps that I used say that you really need to burn in those caps.
Enjoy!
alex,
a thousand people saying that mundorf's need burn-in doesn't mean that it is correct. ;D just enjoy your pre-amp..... ;D
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alex,
a thousand people saying that mundorf's need burn-in doesn't mean that it is correct. ;D just enjoy your pre-amp..... ;D
Tony,
Yes, the never ending debate. My experience with Mundorf, brand new already sounds ok (the ZN and the Mcap, have not used those expensive ones, am CHEAP!)
Edrel just gave me some Wimas, sounds good!
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I just re-did my Monica 2 DAC.
It used to be paired with a grounded grid 6688 that somebody at PDVD did for me. The sound from the DAC and the 6688 grounded grid is sort of bitin, so I installed new PSU with better pi filtering and the 6688 grounded grid using plate chokes, which was called for in the original design. The original PSUs B+ also sags under load and it made the sound kind of flat. After my modification of the PSU, the sound opened up!
Yeo (the designer of the Monica 2 DAC) emailed me and told me there is a new I/V linestage that sounds better than the 6688 grounded grid. So I purchased the PCB and assembled the RB SS I/V stage. I dismantled the 6688 grounded grid and junked the original chassis.
I completely redesigned the PSU, opting for better regulation and better filtering using Aerovox caps and wima polypropylene on the PSU for both the DAC and the I/V stage.
I just finished the soldering at around 9:00 pm last night:
(http://farm3.static.flickr.com/2188/1806055005_e5df5b2372_o.jpg)
The DAC is on the left side top shelf, the tubed preamp on the right top shelf is a 12au7 cathode follower, inspired by the Foreplay 3 design, using 0D3 regulator and well filtered PSU. On the lower shelf is my 832A PP amp driven by a 6J5.
It sounds glorious, my vintage Philips DVD player connected to the Monica DAC sounds better than a tubed CDP!
This weekend, I will sand the wood plinth, use tung oil for finishing, for the alum top plate, I will coat it with baking type automotive clear (from my work at Nippon Paint). ;)
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Update 03 November 2007:
Almost done drilling and cutting the alum top plate of my new tube amplifier:
(http://farm3.static.flickr.com/2160/1839726471_6a78ec1b40_o.jpg)
When done, it will produce a GLORIOUS (hold your breath), 1.0 (ONE) watt of power per channel, hehehehe.....
It is a parafeed circuit, 12b4 tube providing the power and either a 5670 or 6n1p driver. It will be tube rectified using 6X5 rectifier and no electrolytic on the PSU!
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Update 05 November 2007:
Finished assembling the 12b4 amp at 1:00 am today:
(http://farm3.static.flickr.com/2140/1864306220_df1ae49bf3_o.jpg)
(http://farm3.static.flickr.com/2319/1863480405_9389a79c08_o.jpg)
Currently, am using a GE JAN 5670 for drivers. It sounds excellent at ONE watt per channel, but I think I need a more sensitive pair of speakers, my Fostex are just 91db.
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Update 05 November 2007:
Currently, am using a GE JAN 5670 for drivers. It sounds excellent at ONE watt per channel, but I think I need a more sensitive pair of speakers, my Fostex are just 91db.
would an additional 2db in sensitivity be enough? ::)
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would an additional 2db in sensitivity be enough? ::)
Might not be enough, am looking for something more than 97db.
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Might not be enough, am looking for something more than 97db.
into the realm of vintage horns - klipsch altec etc... or perhaps a lowther or living voice ::)
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into the realm of vintage horns - klipsch altec etc... or perhaps a lowther or living voice ::)
I will be trying a pair of Altec 403 and a pair of 97db Philips. I also have source for Corals.
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sir alexg, puwede po ba malaman ung bill of materials ng tube project mo?
ang galing!
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sir alexg, puwede po ba malaman ung bill of materials ng tube project mo?
ang galing!
Sure, but which one? ;D
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sir yung nafeature sa diyaudio
http://diyaudioprojects.com/Tubes/KT88/index.htm (http://diyaudioprojects.com/Tubes/KT88/index.htm)
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sir yung nafeature sa diyaudio
http://diyaudioprojects.com/Tubes/KT88/index.htm (http://diyaudioprojects.com/Tubes/KT88/index.htm)
That one, be careful with the schematic as Gio made a slight mistake on it. If you want I can email you the correct schematic, pm me your email address.
I also sent you pm on the cost of parts.
Regards,
Alex
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A fellow PinoyDVD member asked me to make for him a KT88 SE amp based on my KT88 amp.
Chassis and plinth is almost done, all the irons are wound using Z11 cores (not ordinary recycled Raon cores!) The PP OPT is wound interleaved, 5K primary Z and secondary taps for 4, 8 and 16 ohms. PSU uses CLC filter (the choke is 10H 200ma). Audio grade capacitors (Nichicon, Nippon Chem, and Evox Rifa) will be used on the circuit.
Driver tube is 6n1p using CCS on the cathode. Power tubes can be EL34/KT88/6L6 (but is is optimised for KT88). Triode strapped, it will produce around 7 watts per channel, ultralinear, around 10 to 12 watts per channel (we have not measured it).
Here is the first picture when I was trying to find the most logical layout of the topside components:
(http://farm3.static.flickr.com/2144/1990633145_88d9b81f7d_o.jpg)
The transformers on the top chassis are just mock-up irons used only for drilling holes and doing the cut outs, the real irons will have black endbells and should look nicer.
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Hi alex,
Does the opt has UL tap?
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Hi alex,
Does the opt has UL tap?
Yes, 40% UL tap. Same OPT as the one you heard during the alabang hifi show, from Fetronic (Edrel's) of EPZA, Rosario, Cavite.
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Looks good, Sir alexg. I guess it will also sound great. :)
Congrats to you and the lucky fellow member. :)
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Looks good, Sir alexg. I guess it will also sound great. :)
Congrats to you and the lucky fellow member. :)
Thanks Romy. This will be an almost duplicate of the amp we took to the Alabang Hifi Show last July, we just optimised the power supply and improved the layout so that the heat from the output tubes does not warm the OPT and the choke (I ignored the required clearance of the KT88 when I did my amp) :-[
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Hi alex,
Does the opt has UL tap?
order ka? big discount for you ;D
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lookin good, Alex/Edrel...all lessons learned in the past based on Alexg's KT88 diy experience will benefit this lucky unit....lucky owner too!...just in time to sing the Christmas carols ;)...congrats!
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lookin good, Alex/Edrel...all lessons learned in the past based on Alexg's KT88 diy experience will benefit this lucky unit....lucky owner too!...just in time to sing the Christmas carols ;)...congrats!
Thanks, dana.
Unfortunately, am running behind schedule. Too much year-end work at my office and other distractions, like Christmas shopping! ;D
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After the success of my parafeed 12b4 amp, am working on a parafeed 6080 design.
Originally, I was thinking driving this with a 6n1p, but upon double checking of the circuit and values, I found that the 6n1p will not be able to swing the 6080 to full power. The 6080 needs around 80 to 100volts from the driver. The 6n1p will only delivery around 50 to 55V.
Looking at options, I narrowed it down to 12sl7 and 12at7, driver tubes that I have on my stash. I will be borrowing the power transformer from my 832 amp and it does not have 12v heater tap, so I will be using the 12at7 (which is quite ok, it can deliver more current).
I will be starting this amp soon. I will post pictures soon.
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Alex,
Looking good. Ngayon lang ako nag browse thoroughly kaya ngayon ko lang nakita. This is like the reality show "Pimp My Ride". Yeahhh. Yo da man!
cheers
rq/leonidas
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Update:
I am more than halfway done wiring the amp. Here is the upskirt picture:
(http://farm3.static.flickr.com/2291/2110661918_ccd0bf255c_o.jpg)
Hopefully, it will sing or smoke this weekend. Am still waiting for the painted transformer endbells.
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sir alexg, how much inabot itong project na 'to?
ipopost ba ito sa diyaudioprojects.com?
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sir alexg, how much inabot itong project na 'to?
ipopost ba ito sa diyaudioprojects.com?
This is the same circuit posted on diyaudioprojects.com.
Materials cost a bit more than 20K. Transformers were wound on cores that are Z11, PSU capacitotrs are Nichicon or Nippon Chem and Evox Rifa, no surplus PC PSU caps here. Coupling caps will either be Wima or Mundorf (I found that I like the Mundorf ZN coupling cap for this amp, this mundorf is very reasonably price, I can't hear justifiable difference when using the much more expensive Mundor for coupling). Plate resistors for the 6n1p driver is wirewound, as well as the cathode resistor of the power tube. PSU uses a 10H smoothing choke (10H loaded, 20H unloaded), OPT is oversized (we found that oversized OPT sounds better, but of course cost much more). ;D
I have not tried using lower quality core (H20 and H50, used my most Raon winders) on the PSU. My winder/friend Edrel Sison refuses to use cores that are not Z11 or higher in quality.
Hookup wires are teflon insulated, tinned, OFC copper.
As featured on diyaudioprojects.com, this amp is quite very good for tube rolling (it can use KT88, 6550, EL34, 6L6 for power tubes; and it can use 6n1p and 6dj8 variants for the driver tube). Just imagine the possible combination using different variants of those tubes! ;D
This circuit was the tube amp playing with the Vandersteen 1C at the Alabang Hifi Show last July.
Will post more pictures later today.
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At around 4:30 pm today, I finished this SE KT88 amp. After checking for smoke and melting plastic, which I found none, I proceeded to check the voltages. All voltages are within 10% of specs.
I proceeded to connect it to my system (CD player into a Monica2 DAC with SS I/V stage into a foreplay inspired preamp and my Fostex iBIB speakers).
Powered everything up, absolutely very quiet amp (connected to my 91db speakers), hit play on my CD player and, wow, Diana Krall is singing!
(http://farm3.static.flickr.com/2133/2111905449_b8daae6d4d_o.jpg)
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wow, congrats to you sir alex and to the lucky owner, :o
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gandah! :o
padinig naman! ;D
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wow, congrats to you sir alex and to the lucky owner, :o
Doc, thanks.
gandah! :o
padinig naman! ;D
Sure. BTW, I ordered a pair of 2a3, I want to do a parafeed circuit, and maybe a Sun Audio inspired 2a3 (if I will get lucky and find the schematic ;) )
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Here is the picture of the 6080 parafeed while I was doing my preliminary layout.
(http://farm3.static.flickr.com/2026/2051375093_cf80dcedcb_o.jpg)
I have finished wiring the amp and and it sounded good, the vocals are great, bass is quite tight, but the bass is not as good as the KT88 SE.
For Jazz and vocals it is a great amp, as well as rock!
I will post the latest picture soon. I have not painted the chassis yet, but I am done with the circuit. 12at7 driving the 6080 in a parafeed circuit. I am using a Talema toroidal mains transformer for OPT!
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surely, will send you the schematic! ;D
Doc, thanks.
Sure. BTW, I ordered a pair of 2a3, I want to do a parafeed circuit, and maybe a Sun Audio inspired 2a3 (if I will get lucky and find the schematic ;) )
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AlexG,
Like a father waiting for his newborn child to spring out from the delivery room. This is how I feel. Poging-pogi with the JJs a. Hmmmm hope it mates well with my KEFs and Altecs waiting. Tapos foreplay naman. Perfect.
cheers,
Leonidas/Robert
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AlexG,
Like a father waiting for his newborn child to spring out from the delivery room. This is how I feel. Poging-pogi with the JJs a. Hmmmm hope it mates well with my KEFs and Altecs waiting. Tapos foreplay naman. Perfect.
cheers,
Leonidas/Robert
Somehow on your amp, I like the sound of the ultralinear mode. On mine, the ultralinear is quite boring. Hehehehe...
Your amp sounds great with Siemens EL34! Vocals are to die for, you might want to scout for NOS Siemens EL34. Not too shabby too with JJ El34, but does not sound so hot with the Electro Harmonix EL34 (of course, your preference might be different).
See you Tuesday or Wednesday next week.
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Alex,
Haven't really tried listening in ultralinear mode. My EL34 is Gold Aero. Mahirap maghanap ng nos siemens, will try in Balikbayan me nakita akong siemens 6l6 baka me maligaw na el34. Pwede rin pala ako mag tube roll sa driver. What other types of tubes pwede? Howbout yung rectifier?
robert/leonidas
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Alex,
Haven't really tried listening in ultralinear mode. My EL34 is Gold Aero. Mahirap maghanap ng nos siemens, will try in Balikbayan me nakita akong siemens 6l6 baka me maligaw na el34. Pwede rin pala ako mag tube roll sa driver. What other types of tubes pwede? Howbout yung rectifier?
robert/leonidas
The driver tube is 6n1p, you can use 6dj8 (but don't get the expensive 6dj8 like amperex) you might not like the result (I tried the amperex on mine, did not like the result).
The sovtek 6n1p is the one that will come with the amp, I have another military 6n1p that we got from ebay if you are interested, they cost 600 pesos and are NOS. The Sovtek and the military 6n1p sound quite different.
For a pair of Siemens EL34, I got a pair from Earl Estrera of this forum, pm him, I think he still have a pair, quite expensive but worth every peso that you spend on it.
How many Gold Aero EL34 do you have? Are those NOS?
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Alex,
No idea on my Gold Aero's History. But net searches yielded very positive feedback on the brand some even say they have the best el34's, well that's arguable of course. I will try em with my amp and share my findings. I'll stick with the sovtek 6n1p in the meantime so I can save up for the foreplay.
Robert/Leonidas
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Sir Leonides,
Congrats on your nice new amp!
romymartinez
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Nice seeing you again Robert.
Thanks for the album (CD) of your wife. Her voice is heavenly, I wish she will do another album!
Am also glad that you like your new amp. I will be re-wiring my amp's PSU so I can incorporate what I did on your amp's PSU, I like the clarity and dynamics of your amp better than my amp.
See you again early January for your new tubed audio gear!
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congrats alexg on finishing the amp.
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AlexG,
Tnx. My wife was thrilled with your comments. Her next album will be instrumental with a few guest vocalists to interpret her original compositions. She's more of a piano virtuoso than a singer.
Anyway, I was not able to spend a lot of time with the amp last nyt kse I was dead tired and today am rushing lots of work before christmas break so hassle. Anyway, am still waiting for the full range speakers so I'll reserve my observations muna till I put them together. Right now kinabit ko muna sa Advent3 ko kasi dun pinaka maganda tumunog. Na notice ko lang sa KT88 medyo on the brightside pag Kef ang partner. With your amp kse using 6550 tamang tama lang even with the Kefs. So I guess I would be getting a pair of 6550s soon.
Anyway, tnx for making my audio life more exciting this christmas. Cant wait to see my foreplay!
cheers,
robert/leonidas
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Qbral! talagang Tubero ka na ah! ;D
Congrats & happy holidays to both of you!!! ;D
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Rene.
Oo nga e. simula na to ng walang hanggang wagas!
Happy holidays din sayo at sa lahat!
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It all started when I started exchanging emails with a Kiwi guy (Bruce Ward) who wants to build a copy of my SE KT88 amp based on Mikael Abdellah's design at diyaudio.com.
Bruce works for Tait communication in New Zealand (secured radio designer and manufacturer, these secured communication equipment are used by embassies and other agencies, usually, the black kind), and one day he told me they found a box of NOS tubes at their warehouse. He said the tubes are 6080. Being a very nice guy, Bruce sent me 4 pairs of 6080s and at the same time I bought another 5 pairs from trademe.co.nz (Kiwi's version of ebay.com). I intend to use them as voltage regulators for my projects!
I started reading about 6AS7/6080 and found several people have used these tubes as power tubes for amps, these tubes are designed to be voltage regulators.
I opted to do a parafeed circuit using 12at7 as driver. The project was breadboarded and stayed that way for a few months. This weekend I decided that my parafeed 6080 deserves a better chassis:
(http://farm3.static.flickr.com/2001/2273501928_7b96c42822_o.jpg)
Chassis sanded and fitted on the plinth.
(http://farm3.static.flickr.com/2388/2273505834_dd8856e56d_o.jpg)
Aluminum plate painted with automotive clear polyurethane and the plinth oiled. The two transformers are plate chokes for the 6080.
(http://farm3.static.flickr.com/2349/2273502038_244b1f6007_o.jpg)
Testing the amp. The transformer endbells underneath the plinth is used as temporary feet for the amp (This amps gets very very hot, 2.5A 6.3V 6080 heaters, and the single tube is dissipating almost 24 watts).
It sounds excellent for what it is, a tube regulator for power tube, ordinary toroidal transformer for output transformer!
In all, these amp have 8 transformers consisting of 1 power transformer, 1 smoothing choke and 4 plate chokes! All of the irons are wound on Z11 cores done by Edrel Sison. The OPTs are toroidal power transformers from RS. ;D
Between this and my SE KT88, this amp gets more playtime than my SE KT88.
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Hi alex,
I noticed that there is only one tube, how does it handle the left and right channels ?
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Hi alex,
I noticed that there is only one tube, how does it handle the left and right channels ?
it's a dual triode, 2 sections in one envelope capable of 15watts per plate......there are others like this tube, the 6258, 6336 and the russian 6c33 are other types and have even more power dissipation capability....... ;D
one section, one channel, simplicity is the salient feature of this amp......the use of choke plate loads enables the 6080 tubes to be driven well, a simple resistor plate load will have a hard time with this amp....
good job Alex!
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great work on that plinth alex. very nice wood. this is a very encouraging project!
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Congrats Sir alexg. :)
Ilang watts per channel ito, Sir?
romymartinez
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Ilang watts per channel ito, Sir
between 3 to 6 watts....
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nice work again sir alex, keep on inspiring us with your projects, :)
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I reckon the same principle applies for those tube pre-amps and CD players with single tubes right ?.. always wondered how those things work..
it's a dual triode, 2 sections in one envelope capable of 15watts per plate......there are others like this tube, the 6258, 6336 and the russian 6c33 are other types and have even more power dissipation capability....... ;D
one section, one channel, simplicity is the salient feature of this amp......the use of choke plate loads enables the 6080 tubes to be driven well, a simple resistor plate load will have a hard time with this amp....
good job Alex!
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congrats, nice amp.
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I reckon the same principle applies for those tube pre-amps and CD players with single tubes right ?.. always wondered how those things work..
yes, just to give you an idea, the circuit is a SET(single ended triode) but instead of transformer feeding the speakers directly, the triode is choke loaded, then capacitor coupled output transformer is used....
this output transformer is a torroid power transformer, now since no dc is flowing thru it, the torroid is not subject to saturation the way an output transformer on the set amp is.... plus since the torroid is a wide bandwith device, frequency response is excellent...
actually this technique has long been known but is not implemented in commercial amps for reasons of cost, only DIY'ers do this trick... ;D
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yes, just to give you an idea, the circuit is a SET(single ended triode) but instead of transformer feeding the speakers directly, the triode is choke loaded, then capacitor coupled output transformer is used....
this output transformer is a torroid power transformer, now since no dc is flowing thru it, the torroid is not subject to saturation the way an output transformer on the set amp is.... plus since the torroid is a wide bandwith device, frequency response is excellent...
actually this technique has long been known but is not implemented in commercial amps for reasons of cost, only DIY'ers do this trick... ;D
Thanks Tony.
A member at diyaudio.com posted that he did a KT88 parafeed, this might improve my SE KT88 circuit some more because of the toroid bandwidth, might be worth a try.
Am also contemplating of doing a 2a3 parafeed (very similar to bottlehead.com's Paramour amp) also driven by a 12at7...
Regards.
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Great job alexg....would like to get a chance to hear your creation sometime.
regards,
Joeygs
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A member at diyaudio.com posted that he did a KT88 parafeed, this might improve my SE KT88 circuit some more because of the toroid bandwidth, might be worth a try.
i am sure it will, here is one tube you may want to look at, the 829B: http://www.tubes.mynetcologne.de/roehren/daten/as_triode_e.html (http://www.tubes.mynetcologne.de/roehren/daten/as_triode_e.html)
http://www.tubes.mynetcologne.de/roehren/daten/3e29pentode_as_triode.pdf (http://www.tubes.mynetcologne.de/roehren/daten/3e29pentode_as_triode.pdf)
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i am sure it will, here is one tube you may want to look at, the 829B: http://www.tubes.mynetcologne.de/roehren/daten/as_triode_e.html (http://www.tubes.mynetcologne.de/roehren/daten/as_triode_e.html)
http://www.tubes.mynetcologne.de/roehren/daten/3e29pentode_as_triode.pdf (http://www.tubes.mynetcologne.de/roehren/daten/3e29pentode_as_triode.pdf)
Hi Tony,
Can you point me to triode strapped 832A plate curves? Might take a look at it and do a parafeed 832A... hehehehehe.... I already built the 832A PP, sounds good for what it is but it sounds too harsh for me.
Regards.
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Hi Tony,
Can you point me to triode strapped 832A plate curves? Might take a look at it and do a parafeed 832A... hehehehehe.... I already built the 832A PP, sounds good for what it is but it sounds too harsh for me.
Regards.
i have not seen triode curves for the 832 but i guess they will be more or less similar to 829 albeit lower plate dissipation to about 12watts...
-
Encouraged with the sound of Edrel's 7189 SET amp, I built an EF86 (triode strapped) driven EL84 (7189) parafeed amp.
(http://farm4.static.flickr.com/3032/2503925751_20cc6f675b_o.jpg)
After painting the aluminum plate and varnishing the Dao plinth.
(http://farm4.static.flickr.com/3145/2504756676_323b5e137d_o.jpg)
Before I started wiring the components.
(http://farm4.static.flickr.com/3234/2504756766_6c3c6f0713_o.jpg)
After spending a few hours, now it is singing! One of those moments when the flick of the switch brings music, glorious music, not distortion nor silence like the first time I turned on some of my DIY amps.
How does it sound? Great potential, I will run it in for a few days, but most likely not too much change, maybe a better parafeed capacitor. Maybe try to bias the 7189 (EL84) hotter.
-
Congrats Sir alexg! Looks really nice with those toroids. :)
How many watts? And how does it compare with your other DIY amps?
Regars
romymartinez
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Congrats Sir alexg! Looks really nice with those toroids. :)
How many watts? And how does it compare with your other DIY amps?
Regars
romymartinez
Romy,
EL84 triode strapped is around 1.5 to 2 watts per channel. But it is an excellent 2 watts per channel.
Compared to my other amps, I would put the SE KT88 as number 1, the EL84 and 6080 tied at second. But it is close, I find it hard to rank them. ;D
You are welcome to try them if you want.
Regards,
Alex
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Romy,
EL84 triode strapped is around 1.5 to 2 watts per channel. But it is an excellent 2 watts per channel.
Compared to my other amps, I would put the SE KT88 as number 1, the EL84 and 6080 tied at second. But it is close, I find it hard to rank them. ;D
You are welcome to try them if you want.
Regards,
Alex
Hi Sir Alex,
I guess I should return the 6080 immediately to try them out. :D :D
Regards
romymartinez
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cge sir romy, ibalik mo na at ako naman hihiram ng 6080, hehe
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cge sir romy, ibalik mo na at ako naman hihiram ng 6080, hehe
Doc,
No problem, if you want you and Romy can make arrangement so that Romy can drop off the amp to you on his way to Laguna to pick up the EL84.
Romy,
Am doing another 12sn7/6sn7/7n7 preamp, you are welcome to try the 12sn7 that I have right now, compare it with your foreplay.
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tnx sir, nag pm na ako kay sir romy
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sir, i was looking at your 6080, nasaan dun ung terminals for the speaker cable? parang di ko kasi maintindihan, hehe
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sir, i was looking at your 6080, nasaan dun ung terminals for the speaker cable? parang di ko kasi maintindihan, hehe
speaker cables are at the rear end of the chassis, the plastic on top are banana plugs (black-Left channel, red-Right channel) :)
-
(http://farm4.static.flickr.com/3032/2503925751_20cc6f675b_o.jpg)
sir alexg,
ask lg po if how much did it cost you for this project?
ganda ng pagkagawa ;)
thanks :)
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sir alexg,
ask lg po if how much did it cost you for this project?
ganda ng pagkagawa ;)
thanks :)
I have not accounted the expenses yet, but the transformers (power, smoothing choke, plate chokes and output transformers; total of 6 transformers) already cost me more than 13.5K. I figure additional 4K for the other parts (tubes, caps, resistors, etc).
Parafeed circuits are heavy on the transformers which are expensive, that is why you can hardly find parafeed amplifiers from commercial manufacturers. There is something magical about the sound of parafeed amplifiers, that I really like.
:)
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sir alex, bat di pa ito nakapost sa diyaudioprojects?
galing! kakainspire kayong dalawa ni sir edrel.
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sir alex, bat di pa ito nakapost sa diyaudioprojects?
galing! kakainspire kayong dalawa ni sir edrel.
I have not talked with Gio for a while, I still owe him the 6080 parafeed pictures and schematic. Hehehehehe....
I will try to have this two projects posted at diyaudioprojects.com
Thanks.
-
congrats alex for your another success project! :)
you're way better and moving up to another level! ;D
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@Sir alexg: Big thanks Sir. I would really love to try out your 12sn7 preamp. :D :D
@Doc Sandy: PM sent Sir. :D :D
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@Sir alexg: Big thanks Sir. I would really love to try out your 12sn7 preamp. :D :D
@Doc Sandy: PM sent Sir. :D :D
Sir Romy, Doc Sandy,
swerte nyo naman mapapakingan nyo yan :) :)
sir Alex, galing talaga ng mga creations mo...
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@Sir alexg: Big thanks Sir. I would really love to try out your 12sn7 preamp. :D :D
@Doc Sandy: PM sent Sir. :D :D
Romy,
No problem, I will lend you the 12sn7 preamp.
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Sir Romy, Doc Sandy,
swerte nyo naman mapapakingan nyo yan :) :)
sir Alex, galing talaga ng mga creations mo...
Thanks.
If you want, you can audition the amp too. You just need to pick it up from Sta Rosa, Laguna. ;D
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We were able to buy some inexpensive 12sn7 (equivalent to 6sn7, except for the 12volt heater) tubes.
I always wanted to do a *sn7 preamp, first stage is a simple voltage amp DC coupled to second stage configured as cathode follower. B+ is around 300VDC. PSU is tube rectified using 6x5 rectifiers, with a 10H smoothing choke, 2X Nippon Chem 150uf caps, and 4 pieces of non-electrolytic caps. Volume pot is an Alps 100K blue potentiometer.
I also used some custom fabricated aluminum chassis that a metal fabrication company made for us: (sorry about the quality of the pictures, am using my cell camera, my Minolta has no battery and my Nikon has not arrive yet.) ;)
(http://farm4.static.flickr.com/3264/2513046841_de6dcc55dd_o.jpg)
The aluminum chassis as it came from the fabricators.
(http://farm3.static.flickr.com/2060/2513878348_63016edd61_o.jpg)
The back view with the installed IEC socket.
(http://farm3.static.flickr.com/2088/2513880090_37ffef6f79_o.jpg)
Bottom view with the perforated bottom cover for ventilation.
(http://farm3.static.flickr.com/2244/2513871262_30aff59456_o.jpg)
My first project using the chassis, the 12sn7 preamplifier. The Dao front plinth needs to be planed some more, it is quite too thick for my taste, maybe this weekend.
(http://farm4.static.flickr.com/3234/2504756766_6c3c6f0713_o.jpg)
The preamp with my EF86-EL84 parafeed amp (the preamp is the below the amp.)
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excellent work of a preamp! i really love that dao wood :)
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Congrats Sir alexg. Another fine-looking work of art. :D :D
How does this sound compared with your other DIYed preamps?
Regards.
romymartinez
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Congrats Sir alexg. Another fine-looking work of art. :D :D
How does this sound compared with your other DIYed preamps?
Regards.
romymartinez
Hi Romy,
You will have a chance to audition this and compare to your 12au7 preamp.
Regards,
Alex
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I have built similar preamp before, Foreplay inspired 12au7 preamp. But this time, I decided to go tube all the way, tube rectified (6X5GT), tube regulated using 0D3.
PSU is CLCRC filter which makes the preamp dead quiet. I also decided to use one tube for the voltage amplifier stage (VA) and one tube for the cathode follower stage (CF). This allows for a much better tube rolling option, I can use one kind of 12au7 for the VA stage and another for the CF stage. The original design needs a pair of the same kind of tube for tube rolling!
PSU caps are Nippon Chem bypassed by wima polycarbonate caps. Output capacitor is Mundorf MCap (am cheap, don't want to spend on the more expensive Mundorfs.) ;D
Here are the pix of the build process:
(http://farm4.static.flickr.com/3130/2599057649_683c42db52_o.jpg)
Metal work, I used drill bits from vt4c.com to cut the socket holes and I used my trusty jigsaw to cut the power transformer mounting hole.
(http://farm4.static.flickr.com/3087/2599058061_a1f4d82ea5_o.jpg)
After painting the alum chassis with Nippon automotive polyurethane clear, I started to mount the components. The blue toroidal is my heater supply and the transformer on the left is the PSU choke.
(http://farm4.static.flickr.com/3164/2599887550_7d7f3d16bd_o.jpg)
The preamp making music the first time I connected it to my tube amp. The rear octal tube is the 6x5GT rectifier, the tube in front of it and in the middle is the 0D3 voltage regulator, the small tubes in front are the 12au7, the one on the left is an RCA blackplate (voltage amplifier) and the one on the right is a Tungsol (great combination). The IC on the front RCAs are DIY SOTA with eichmann RCA plugs.
(http://farm4.static.flickr.com/3143/2599887862_f74ab894e1_o.jpg)
The nice purplish glow of the 0D3 gas voltage regulator.
(http://farm4.static.flickr.com/3228/2599888246_a6e5029975_o.jpg)
(http://farm4.static.flickr.com/3046/2599888610_e5e98cd5f1_o.jpg)
Connected to my EF86-EL84 parafeed amp.
(http://farm4.static.flickr.com/3165/2599888950_ba29fb3f51_o.jpg)
(http://farm4.static.flickr.com/3194/2599060267_0c80591e94_o.jpg)
Some more photos of the preamp.
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sir alex, congrats uli, ang dami mo nang mga creations, this one looks just as good as the others, im sure this one sounds great ;D
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ganda nito sir ng creation mo... malinis at astig ang dating! :o :o
congratz!... ;D
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Hey, nakakarami ka na, ah.
Pang ilan na ba yan? ;D
Bumabagyo na nga, bagyo rin yang dala mo.
Congrats again and sa mga nakapila pang projects.
Should you need a babysitter,im just here ;)
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Hey, nakakarami ka na, ah.
Pang ilan na ba yan? ;D
Bumabagyo na nga, bagyo rin yang dala mo.
Congrats again and sa mga nakapila pang projects.
Should you need a babysitter,im just here ;)
your turn to do your own! i have the chassis here, some transformers and parts, connect it, in 2 days you can have it all ready! :) :)
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Looks gorgeous. Congrats! Sir! ;D
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your turn to do your own! i have the chassis here, some transformers and parts, connect it, in 2 days you can have it all ready! :) :)
hehe, sayo naman tlaga galing halos lahat mga tube diy parts e ;D
so many toys, too little time...
work in progress yung mga kids,parang diy rin, may mga gastos pa...
also, naghihintay ng big inspiration para makapag diy ulit...
para di OT, Alexg may we know the ffg:
1. who made those transformers & chokes? ;D
2. tama ba,the OD3 acts as your voltage regulator,@150Vdc?
3. what is the output sensitivity of this latest preamp of yours?
btw, nice touch on those circular see saw power switch on the side ;)
:)
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hehehehe...
All irons from Edrel Sison. 0D3 regulates the B+ to 157VDC. I have not computed the output sensitivity, but input sensitivity is around 1.2 volt (your CD player at 2volt will drive this preamp).
I have been tube rolling and the best combination so far is RCA blackplate on the voltage amplifier section (VA) and tungsol 12au7 on the cathode follower section (CF). I also have nice result with RCA cleartops on the VA section and tungsol 12au7 on the CF stage. GE 6189 also is quite nice on the VA stage with the RCA blackplate on the CF stage. Being able to use two different kind of 12au7's for this preamp is a tube rollers' "heaven."
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feature natin sa 08 Alabang Audio Fair. see link below:
http://pinoydvd.com/board/index.php?topic=81006.0
cyber
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feature natin sa 08 Alabang Audio Fair. see link below:
http://pinoydvd.com/board/index.php?topic=81006.0
cyber
Yes, we are planning to bring it with us, together with some other DIY tubed equipment. :)
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This is very good AlexG.....see you and your gears at the Alabang Fair
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Yes, we are planning to bring it with us, together with some other DIY tubed equipment. :)
And DIY speakers as well? ;D ;D
Regards
romymartinez
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And DIY speakers as well? ;D ;D
Regards
romymartinez
My DIY Viech speaker is not painted yet so I might not bring it (looks quite bad with raw MDF showing). ;D
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The DIY Room will feature works of AlexG , Edrel Sison and the rest of their DIY team. So don't miss it.
Am trying to secure the last pair of Triangle Celius FS (AT 92db) to complement their SET amps.
The final invites will be distributed starting next week. This one promises to be BIGGER, BETTER and FRIENDLIER!!
(http://img.photobucket.com/albums/v225/cybermms/08AlabangAudioFair_Final2_jpeg.jpg)
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sana libre ako para makapunta! ;D
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Here are pictures of my RJM phonostage using 6n1p instead of 6dj8/6922:
(http://farm4.static.flickr.com/3241/2694744329_8ab106603a_o.jpg)
The RJM phonostage with 6n1p tubes.
(http://farm4.static.flickr.com/3247/2695562468_268ab15634_o.jpg)
On the left (upper shelf) is my 12au7 VA/CF preamp, on the right (black chassis) is my RJM phonostage and below is my EL84 driven EL84 parafeed amp.
This phonostage, though using AC heaters is quiet as a mouse. The sound is much better than the RJM's VSPS (very simple phonostage, cloned by some DIYers on this forum). I have tried this with 6dj8 and 6922 tubes, and I like the sound of the 6n1p a lot better.
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congrats alex! grabe ang sipag mo gumawa ah! ;D
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congrats alex! grabe ang sipag mo gumawa ah! ;D
Thanks. Life is too short not to do tubed equipment. ;D
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As usual, mukhang maganda na naman yan ah.
Ano gain nyan sir?
Pag nagawi yan ng QC, pakinggan natin :D
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As usual, mukhang maganda na naman yan ah.
Ano gain nyan sir?
Pag nagawi yan ng QC, pakinggan natin :D
Dana, medyo lowish yung gain computed at around 38 to 40db, I have not measured it.
Pwede ma-audition yan sa QC. I might bring it sa Alabang Audio Show.
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very very nice 8)
congrats sir alex
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Sir Alex,
Ganda talaga ng mga creations mo... sama ako kay Dana pag nagawi yan sa QC.. ;D
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very very nice 8)
congrats sir alex
Sir Alex,
Ganda talaga ng mga creations mo... sama ako kay Dana pag nagawi yan sa QC.. ;D
Thanks guys.
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Sir alexg,
Congrats!
;D ;D ;D
Regards
romymartinez
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Hi Romy,
Thanks! You need to get into analog too!
Regards,
Alex
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I am not sure if there is a seperate thread for this.
Congrats Sir Alex, ginulat mo nanaman kami!! ;D ;D
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I am not sure if there is a seperate thread for this.
Congrats Sir Alex, ginulat mo nanaman kami!! ;D ;D
Eto ba yun?
(http://img.photobucket.com/albums/v225/cybermms/08%20Alabang%20Hi-Fi%20Show/08HiFiShow_DIYers.jpg)
(http://img.photobucket.com/albums/v225/cybermms/08%20Alabang%20Hi-Fi%20Show/08HiFiShow_2wSET_AlexG.jpg)
(http://img.photobucket.com/albums/v225/cybermms/08%20Alabang%20Hi-Fi%20Show/08HiFiShow_2wSET1.jpg)
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Wow, I again missed this event. Anyway congrats Sir Alex, Edrel and the rest of the DIYer. And also congrats to Sir Cyber for again organizing the event. :D ;D
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nakakatuwang isipin...
napadaan ako last saturday medyo konti ang tao at wala akong kakilala... di na mahalaga yun, ang sa akin e makiusyoso lang naman.
contrasting scene i noticed:
- DIY room was parang kawawa, hehehe... komo DIY electric fan ang gamit HAHAHA!!! ;D ;D ;D
- others naka A/C at carpet, tapos branded syempre at ang popogi ng gears :o :o :o
BUT... WOW! mas daig ng Pinoy ang dayuhan. congrats PDIYers ;)
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More photo - with the little "paradigm" but with a big voice from the SET amp.
(http://img.photobucket.com/albums/v225/cybermms/08%20Alabang%20Hi-Fi%20Show/IMG_2837.jpg)
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rewiews naman po sa mga nakadalo :D
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Wasn't able to post this sooner... featured in the Alabang Audio Fair - DIY Room (08.08.08) ;)
(http://farm4.static.flickr.com/3164/2859501973_4350a17da7.jpg?v=0)
(http://farm4.static.flickr.com/3136/2859501301_db6084a998.jpg?v=0)
(http://farm4.static.flickr.com/3268/2860330790_be5af6cc71.jpg?v=0)
(http://farm4.static.flickr.com/3226/2859491615_07720cce83.jpg?v=0)
:-*
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Late post.. hehe.. ;)
Featured in the Alabang Audio Fair - DIY Room (08.08.08)
(http://farm4.static.flickr.com/3128/2859500221_8043f8d2d3.jpg?v=0)
(http://farm4.static.flickr.com/3243/2859497155_ab89354912.jpg?v=0)
:-*
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Huli man daw at magaling... huli pa rin! ;D
Featured in the Alabang Audio Fair - DIY Room (08.08.08)
(http://farm4.static.flickr.com/3137/2859500775_2598d3a0ed.jpg?v=0)
(http://farm4.static.flickr.com/3030/2859494743_46a7091db6.jpg?v=0)
:-*
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man o man! i heard this babies with the fostex speakers at the kitchen!
i only have one thing to say!
I BELIEVE!
mabuhay ang DIYers!
Here's the fostex... ;D
(http://farm4.static.flickr.com/3135/2860326512_d30e0e6035.jpg?v=0)
(http://farm4.static.flickr.com/3095/2859497709_63b6e04458.jpg?v=0)
;)
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great combination!
i love the wood grains on those!
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Congrats Sir, Very nice :)
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I have built DACs from kits and have been reading a lot about tweaking CD players, but I did not have the courage to butcher my CD players.
Early this year, I was able to buy a very decent, excellent sounding Denon CD player, it is so inexpensive that I felt so encourage to tweak it.
First thing that I did was replaced the PSU capacitors to Aerovox electrolytics, noticeable improvement on sound. Encouraged, I replaced the electrolytic output capacitor with a very inexpensive Wima MKP (polypropylene), and wow, better dynamics, bass improved. Next was the removal of muting transistors, with trembling hands, I removed the 4 muting capacitors (on hindsight, I should just have wired the output caps directly to the RCA sockets, simpler and safer!)
Encouraged again, I figure I will replace the opamp output stage with a tubed output stage. So I took note of the DAC of my vintage CD player, it is the Burr Brown PCM61P, 18-bit DA converter, 8X oversampling. This particular DAC (lucky for me) has both Io (current output) and Vo (voltage output), which means the opamp is built in into the DAC. Every DIYers on the net says that the best is to tap from the Io (current output) of the DAC, build an I/V (current to voltage converter) and feed the signal to the grid of the tube stage.
After a few weeks of research, I decided to use my favorite 9-pin tube, 6n1p (beside from being CHEAP, it sounds great).
According to the data sheet of the PCM61P, the Io is capable of 1V output, so I really don't need a lot of gain.
After wiring and soldering the tube stage, power up the CDP, it sounded so awful, no mids and no bass, just shrill noise. Back to the drawing board, after a couple of weeks of banging my head (this is my first SS into a tube stage project), I decided to isolate the current output of the DAC totally from the circuit and tied all the opamp input of the DAC to ground (reduce noise), voila, music! A lot better! After a week or so, I decided to tweak the I/V converter, and wow! Sound worth all the effort and time I put into it.
Here are some pictures:
(http://farm3.static.flickr.com/2117/2933545867_a4050158fd_o.jpg)
Now, the only tweak I needed to do is to have the scratched chassis painted at my work (Nippon Paint), flat black, or maybe some nice Honda color.
(http://farm4.static.flickr.com/3270/2933545871_63a3dcfcfd_o.jpg)
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Lot of effort but worth it.
Great work.
A big accomplishment
congratulation
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Lot of effort but worth it.
Great work.
A big accomplishment
congratulation
Hi Bey, when will you be in town?
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Congratz brother ALEX !!!!!
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wow sir alex... this is incredible :o
galing
-
Bass_nut, AudioAmplified, thanks!
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Hello Alex,
Schedule kong umuwi sa 7th November.
Hope to see.
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Sir alexg,
How does it sound campared to other CDPs?
Another excellent work. Congrats!
Regards,
Romy
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Sir alexg,
How does it sound campared to other CDPs?
Another excellent work. Congrats!
Regards,
Romy
The sound is comparable to other commercial tubed CDP.
Compared to the original sound of the same Denon CDP, the tubed analog output is better for my ears.
You are welcome to try it out after I finalize the circuit and make the wires "safer." You don't want 240VDC on the chassis... ;D
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Alex,
Wow nice work.
:)
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This is so nice! Wish I had the same skills in making one of these. Can you make these mods 'commercially accessible'? He he, just asking, I have 2 denon cdps kasi.
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This is so nice! Wish I had the same skills in making one of these. Can you make these mods 'commercially accessible'? He he, just asking, I have 2 denon cdps kasi.
What models do you have? If they are quite old, then I would consider making the modification for you. What amp and speakers are you using?
Where do you live? Maybe you can listen to my tubed CDP and see if you will like it.
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Hi ALex
Does the solid State output still works ?
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This is so nice! Wish I had the same skills in making one of these. Can you make these mods 'commercially accessible'? He he, just asking, I have 2 denon cdps kasi.
Ako dalawa rin, he he ;D, a DCD-670 with PCM67P-K and DCD-1610 with 2 x PCM64P. ;D
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What models do you have? If they are quite old, then I would consider making the modification for you. What amp and speakers are you using?
Where do you live? Maybe you can listen to my tubed CDP and see if you will like it.
I have a dcd790 and a dcd1510. With either i use a Behringer Ultramatch Pro DAC, Mission 702e FS, Yamaha 85wpc stereo integrated (I forgot the model na). I live in Makati, near kamagong/p tamo. Where's your loc? Would love to hear your tubed cdp! ;D ;D ;D Thanks Alex!
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I have a dcd790 and a dcd1510. With either i use a Behringer Ultramatch Pro DAC, Mission 702e FS, Yamaha 85wpc stereo integrated (I forgot the model na). I live in Makati, near kamagong/p tamo. Where's your loc? Would love to hear your tubed cdp! ;D ;D ;D Thanks Alex!
I live in Sta Rosa, Laguna. Sent you PM.
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sir alexg,
Can you do mods for an old nad cdp?
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sir alexg,
Can you do mods for an old nad cdp?
Which model?
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galing... ;D
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Hi ALex
Does the solid State output still works ?
I have to completely disable the solid state output. I could have installed a switch that will allow for either the tubed output and the solid state output to work. Thanks for the idea! ;D
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hello alexg
i have a marantz 4000 which i think is the cdp used for the ah njeo tjeob 4000 modified tube cdp. will you be so kind as to convert my marantz? ;D
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hello alexg
i have a marantz 4000 which i think is the cdp used for the ah njeo tjeob 4000 modified tube cdp. will you be so kind as to convert my marantz? ;D
I will check and get back to you. What tubes were used with the ah njeo tjeob?
Please PM me your cell phone number. Thanks.
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hello alexg
i have a marantz 4000 which i think is the cdp used for the ah njeo tjeob 4000 modified tube cdp. will you be so kind as to convert my marantz? ;D
I checked out the marantz 4000 CDP, it is using a philips DAC, quite simple to add a tubed output stage. hehehe...
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sir alex i have a teac pd 265 cdp, baka puede pa mods din sir.
thanks.
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sir alex i have a teac pd 265 cdp, baka puede pa mods din sir.
thanks.
Let me check if I can find info on your CD player.
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long time no post!
parang kilala ko yung cdp na yun ah...
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long time no post!
parang kilala ko yung cdp na yun ah...
kung saan-saan ka nagsusuot, may talent ka sa cdp tweaking, gamitin mo dito ;D
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how much kaya mag pamodify ng sony 227 esd?
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long time no post!
parang kilala ko yung cdp na yun ah...
Hehehehe... ;)
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baka pwede buy ko nalang yung denon cdp
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just PM me if your selling it kasi i am planning to buy a tube cdp anytime if the price is right or a cd tube buffer.
thanks
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After three days of wiring point-to-point, I just finished my Aikido phonostage. ;D
8 peanut tubes, sounds much better than my 12at7 phonostage and a borrowed clone phonostage. ;)
Pix next time, am enjoying the music (Denon turntable, aikido phonostage, aikido octal preamp, 2a3 SE amp and Corals speakers).
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After three days of wiring point-to-point, I just finished my Aikido phonostage. ;D
8 peanut tubes, sounds much better than my 12at7 phonostage and a borrowed clone phonostage. ;)
Pix next time, am enjoying the music (Denon turntable, aikido phonostage, aikido octal preamp, 2a3 SE amp and Corals speakers).
wooow... congrats... been dreaming of having one ::)
can't wait to see the pics ;D ;D ;D
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Wow! Congrats Sir alexg!
Pics naman dyan! ;D
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After finishing two versions of octal aikido preamp (12sl7/12sn7 and 7n7/12sn7), I was crazy enough to make an aikido phonostage.
An aikido phonostage is nothing but two aikidos with an RIAA passive equalization in between. I ended wiring it so that the input tube of both aikidos can take, 12ax7, 5751 and 12at7, outputs takes the 12au7 family. (This give me headaches on tube rolling, so much combination :devil: )
Both of my Aikidos are wired P2P!
Here are the pix:
(http://farm4.static.flickr.com/3528/3936243073_cf2c309777_o.jpg)
Aikido phonostage with Dao front panel.
(http://farm3.static.flickr.com/2542/3936243005_a94669faf9_o.jpg)
Playing with the octal aikido. (I have not oiled the Dao front panel of the Octal Aikido preamp).
The Aikidos plays well with my 2a3 SE (parafeed with 6n1p input and 12b4 driver) and my Denon TT.
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HANEP! congrats sir alexg!
aside from p2p at hiwalay psu, pareho ba neto> http://glass-ware.stores.yahoo.net/aiphpcb.html
btw may i ask magkano inabot ng 12sn7 based aikido preamp mo? (out of stock yun pcb sa
http://glass-ware.stores.yahoo.net/aikampocboar.html ) ::) :)
edit/add:
tnx sa pm :)
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nice.what's the phono gain? :)
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nice.what's the phono gain? :)
o.t.
sir dana. umpisahan na ang 12sn7 preamp!!! nakatengga 6/12sn7's mo ;D
http://www.tubecad.com/Octal_Aikido_PCB.pdf
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nice.what's the phono gain? :)
40+db if using 12at7/5751 on the inputs, 50+db if using 12ax7, combination of the 12at7/12ax7 will yield gain in between.
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wow !!! very nice finished project sir Alex !!! congrats !!! 8)
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wow !!! very nice finished project sir Alex !!! congrats !!! 8)
Thanks Doc.
I have been soldering to keep my mind off things that I should not be thinking about. ;)
Hope you are doing fine.
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we are ok.. i also wish you will gather more positive energy as days and weeks flow forward sir Alex ..keep on doing those excellent audio stuff as our hobby is an excellent route to re-focus to brighter days 8)
kindly please keep on-line at PinoyDVD ... our very kind hearted buddies are here 8)
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40+db if using 12at7/5751 on the inputs, 50+db if using 12ax7, combination of the 12at7/12ax7 will yield gain in between.
ayuz alexg.
@ 50db gain, am estimating gain from 130 to 400mv using 1mv ~3mv mm cart.
line pre amp is also an option.
ojofool....noted.
solved for now sa phono stage ng mga ss integrateds ko.
also, satisfied so far sa tube phono stage ko.
pag kumpleto parts, patulong tayo...
need control in this hobby. else, we end up as ojofools ;D (di pa ba?...)
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ojofool....noted.
solved for now sa phono stage ng mga ss integrateds ko.
also, satisfied so far sa tube phono stage ko.
pag kumpleto parts, patulong tayo...
need control in this hobby. else, we end up as ojofools ;D (di pa ba?...)
self-explanatory, "kailangan pa ba imemorize yan?" ;D ;D ;D
ipon muna ako parts para sa "12sn7"
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Ganda! ;D
Congrats Sir alexg. ;D
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congrats alex! :)
how silent does the phonostage has? you may try to use 7025 tubes and you will know why frank de grove prefer this over other variant of 12ax7 tubes! ;D
After finishing two versions of octal aikido preamp (12sl7/12sn7 and 7n7/12sn7), I was crazy enough to make an aikido phonostage.
An aikido phonostage is nothing but two aikidos with an RIAA passive equalization in between. I ended wiring it so that the input tube of both aikidos can take, 12ax7, 5751 and 12at7, outputs takes the 12au7 family. (This give me headaches on tube rolling, so much combination :devil: )
Both of my Aikidos are wired P2P!
Here are the pix:
(http://farm4.static.flickr.com/3528/3936243073_cf2c309777_o.jpg)
Aikido phonostage with Dao front panel.
(http://farm3.static.flickr.com/2542/3936243005_a94669faf9_o.jpg)
Playing with the octal aikido. (I have not oiled the Dao front panel of the Octal Aikido preamp).
The Aikidos plays well with my 2a3 SE (parafeed with 6n1p input and 12b4 driver) and my Denon TT.
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congrats alex! :)
how silent does the phonostage has? you may try to use 7025 tubes and you will know why frank de grove prefer this over other variant of 12ax7 tubes! ;D
The phonostage does not contribute hum/noise on my setup (*sn7 aikido preamp and 2a3 SE, both are very quiet too, I need to be around 6 inches on my high sensivity Corals to hear the hum).
;D
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Hi Alex,
the aikido has very good PSRR, noise whould be very low indeed...the aikido is not about tubes used, but about topology. Broskie designed this circuit to be forgiving of tube shortcomings.... ;D
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congrats alex! :)
how silent does the phonostage has? you may try to use 7025 tubes and you will know why frank de grove prefer this over other variant of 12ax7 tubes! ;D
I will try to get some 7025, I have tried 5751, 12ax7 and 12at7 and variants, still prefer the sound of the 12at7, better bass, but the 5751 seems to give better mids.
With 8 tubes, this phonostage is a tube roller's nightmare! ;D
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let me know once you compare it with other variants. :)
I will try to get some 7025, I have tried 5751, 12ax7 and 12at7 and variants, still prefer the sound of the 12at7, better bass, but the 5751 seems to give better mids.
With 8 tubes, this phonostage is a tube roller's nightmare! ;D
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A friend wanted me to build a Foreplay inspired preamp for him.
Here is the preamp build, documented with pictures:
(http://farm3.static.flickr.com/2530/4082938088_4d3f06a50c_o.jpg)
Planing the board that my friend provided, beautiful wood locally called Balayong, very similar to rosewood.
(http://farm3.static.flickr.com/2551/4082177677_07ac5b5a24_o.jpg)
Trimming to size.
(http://farm3.static.flickr.com/2550/4082178293_4443824eb2_o.jpg)
Rebated with a router for the aluminum plate, cut with my miter saw, then glued and clamped. Glue should be dry by tomorrow.
(http://farm4.static.flickr.com/3526/4082178537_95a479f543_o.jpg)
I am being supervised by my boxer named Nala.
Tomorrow, sanding the Balayong plinth and trimming the aluminum plate, boring the socket holes and ptx opening as well as the RCA and IEC sockets. Then sanding the aluminum plate, then finishing it, maybe flat black automotive paint or anodized flat black.
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nice work alex, I think your friend is very very much excited on the outcome of this project :D
Am so sure he cant sleep tonight and waiting for the development tomorow ;D
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i probably know who this friend is. ;D ;D
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He wants the best for his preamp, even the aluminum plate will be replaced with machined brass plate! :o
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He wants the best for his preamp, even the aluminum plate will be replaced with machined brass plate! :o
woah, your friend (and my friend) is a rich guy! ;D ;D
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pa-update sir Alex ;D
and congrats to your very lucky friend !!! ;)
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Sir alex, can you post a pic of the 2a3 amp, ty :)
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Lucky friend indeed! ;D ;D ;D
Congrats Sir alexg and to your friend! ;D ;D
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Sir alex, can you post a pic of the 2a3 amp, ty :)
I am building a monoblock 2a3, that is the picture that i will be posting. hehehehe....
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woah, your friend (and my friend) is a rich guy! ;D ;D
Our friend has the copper plate machined now, we are waiting for the RCA sockets. He already got the Mundorf electrolytics for the PSU.
In the meantime, he heard my 7n7/12sn7 aikido preamp and he wants to hear a 12au7 aikido preamp, so I am breadboarding a 12au7 aikido (I would also like to hear a 12au7 preamp ;D).
I am thinking that this built might go the aikido route instead of the foreplay!
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Hi Alex,
Parang nag-pre-preamp rolling ah......good luck and most of all enjoy. :) :) :)
Regards,
JoeyGS
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Finally finished prototyping the preamp:
(http://farm3.static.flickr.com/2520/4138789795_0f6dfb8e1e_o.jpg)
High quality sockets.
(http://farm3.static.flickr.com/2541/4138438585_b301e5cf79_o.jpg)
The VR150 with the nice purplish glow.
(http://farm3.static.flickr.com/2709/4138785245_4b03c830e3_o.jpg)
The tube rectifier and the VR150.
Lush midrange and airy highs, very tight bass.
Once again, thanks Edrel for those excellent irons!
Mundorfed power supply, auricap output capacitors, Dale resistors... this might be the best preamp that I have built so far!
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Hi alex,
pwede ko ba ipost yung wip aikido ko? baka sakali me mabuo this time.... ;D
eto yung volume control
(http://i5.photobucket.com/albums/y155/leoman53/aikido/02012010094.jpg)
power traffo:
(http://i5.photobucket.com/albums/y155/leoman53/aikido/02012010099.jpg)
chassis: hirap pala butasin yung aluminum chassis ni edrel ang kapal, nga pala pina zinc chromate plate ko yung chassis, bukas pa makukuha
(http://i5.photobucket.com/albums/y155/leoman53/aikido/02012010100.jpg)
(http://i5.photobucket.com/albums/y155/leoman53/aikido/05012010123.jpg)
(http://i5.photobucket.com/albums/y155/leoman53/aikido/05012010124.jpg)
6CM7 at 5687 ang gagamitin kong tubes, maglalagay ako ng bass and trebble controls......yikes!!! ;D ;D
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Cool project.
Just post it if you want. ;D
Nasa Philippines ka?
Point-to-point wiring? 6cm7 for input 5687 for output? Can you please send me schema?
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Cool project.
Just post it if you want. ;D
Nasa Philippines ka?
Point-to-point wiring? 6cm7 for input 5687 for output? Can you please send me schema?
nasa pinas ako ngayon....gagamit ako ng pcb..... ;D
nakuha ko na yung chassis, mura lang ang pa zinc-chromate ng chassis, bale 120pesos.....
6CM7 ang output stage....5687 to drive the tone stack.....lalagyan ko ng option na ma bypass yung tone control...
circuit ni broskie ang gamit ko....nga pala meron pang nabibileng 1.2k carbon comp. resistors sa southern, galing ako doon kanina, tig 2.50 ang isa...
solid state ang psu, merong mosfet cap multiplier....
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tony just how exactly does a zinc chromate finish look? can you post pics?
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eto yon: silver finish, pero merong yellowish na katulad nung endbells ni deeco...mahal ang aabutin kung anodized at saka walang malapit na anodizing shop dito sa pasig....
(http://i5.photobucket.com/albums/y155/leoman53/aikido/CIMG8476.jpg)
assembled na:
(http://i5.photobucket.com/albums/y155/leoman53/aikido/CIMG8478.jpg)
ng-add ako ng nuts para sa screws:
(http://i5.photobucket.com/albums/y155/leoman53/aikido/CIMG8479.jpg)
(http://i5.photobucket.com/albums/y155/leoman53/aikido/CIMG8482-1.jpg)
(http://i5.photobucket.com/albums/y155/leoman53/aikido/CIMG8486.jpg)
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nice one tony! better start your own tony's DIY thread... ;D ;D
and i am looking to start a transformer thread, to help people out there to make simple chokes and traffo..
so back to the thread topic, i wonder what alex is cooking up right now.
i know he has few projects going on.
mind to post update alex? ;D ;D
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nice one tony! better start your own tony's DIY thread... ;D ;D
and i am looking to start a transformer thread, to help people out there to make simple chokes and traffo..
so back to the thread topic, i wonder what alex is cooking up right now.
i know he has few projects going on.
mind to post update alex? ;D ;D
sali ako dun sa transformer thread..... ;D
parang busy si alex sa software presentation sang-ayon sa facebook nya.... ;D
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nice one tony! better start your own tony's DIY thread... ;D ;D
and i am looking to start a transformer thread, to help people out there to make simple chokes and traffo..
so back to the thread topic, i wonder what alex is cooking up right now.
i know he has few projects going on.
mind to post update alex? ;D ;D
Hi Edrel.
So far I have done these:
1. Built an SE EL84, 12at7 input/driver, sounds great! This is the best bang for the buck tubed amp I have ever built.
2. I have prototyped several 2a3 SE amp, using the following for input/driver: triode strapped EL84, 5842 (cap coupled and interstage coupled, the interstage version sounds excellent, but the Lundahl 1660s will break the bank), 6n1p input-12b4 driver (this sounds ok, but a bit confused), 6n1p input-6s4a driver (sounds similar to the 6n1p-12b4), 12at7 and 5687/7119. I did the 12at7 first using plate resistor, after all my iterations I went back to the 12at7 using plate chokes and I think for price/performance, this is the best combo, next is the 5687/7119 input/driver.
3. I have prototyped the following aikido circuits: 12au7 input/12au7 output, 6n1p input/12au7 output, 6cg7 input/5687 output, 6cg7 input/7119 output. Best combination I got is United 6cg7/Sylvania JAN 5687 and United 6cg7/Amperex 7119 (very close) and second best is 12au7/12au7.
4. I have prototyped a 5842 preamp using a transformer output (sounds too HiFi to me, hehehehe...)
5. I am currently working on a TV tube for output tube on an SE amp (tube will remain nameless until am done) ;)
6. Next project might be an Octal aikido phonostage (I already built a nine pin aikido phonostage which is better than most commercial phonostage).
Am too busy. I have accepted to do an SE KT88 for Romy Martinez a couple of years ago, and I have just cut the aluminum chassis (previous, Edrel is out of tranny cores). I will do my best to finish this ASAP.
Am also doing a 2a3 SE amp for Bey, I just finished the prototype a couple of weeks ago (12at7-2a3 SE), time to order irons from Edrel.
Tony,
sali ako dun sa transformer thread..... ;D
parang busy si alex sa software presentation sang-ayon sa facebook nya.... ;D
I am in the middle of a software project for our company (a comprehensive software system to manage all aspect of our operation). So there are a lot of presentation from our vendor which I need to look at, scrutinize, approve/disapprove, manage budget, etc. This is taking a toll on my tube projects. >:(
Anyway, I hope to finish this project within the year (we started early last year). This project is the first in the country to use an open source ERP for a company our size!
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5. I am currently working on a TV tube for output tube on an SE amp (tube will remain nameless until am done)
hey alam ko yata yan ahhh... ;D ako rin meron, pero quiet lang muna tayo....
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lupit! ;D
miss ko na mag diy! :)
eto yon: silver finish, pero merong yellowish na katulad nung endbells ni deeco...mahal ang aabutin kung anodized at saka walang malapit na anodizing shop dito sa pasig....
(http://i5.photobucket.com/albums/y155/leoman53/aikido/CIMG8476.jpg)
assembled na:
(http://i5.photobucket.com/albums/y155/leoman53/aikido/CIMG8478.jpg)
ng-add ako ng nuts para sa screws:
(http://i5.photobucket.com/albums/y155/leoman53/aikido/CIMG8479.jpg)
(http://i5.photobucket.com/albums/y155/leoman53/aikido/CIMG8482-1.jpg)
(http://i5.photobucket.com/albums/y155/leoman53/aikido/CIMG8486.jpg)
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lupit! ;D
miss ko na mag diy! :)
Hi Andy, musta? Mas maraming diy parts where you are now! (Nasa Singapore ka pa rin?)
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Just finished re-plinthing my Denon turntable and I will post pictures soon.
I also finished breadboarding this amp:
7119/5687 input/driver into a Lundahl LL1660S interstage/phase splitter and EL84 triode strapped PP output. Sounds good to my ears.
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congrats bro Alex !!! 8)
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congrats sir! galing talaga! ;D
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Hi alex,
Ok lng and im still here in SG.
Finally, dumating na yung clone sun2a3 ko d2 at malamang may pagkakaabalahan na nman! ;D
Hi Andy, musta? Mas maraming diy parts where you are now! (Nasa Singapore ka pa rin?)
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s2kov, how are you man..
sent you a message regarding the pcb maker's contacts..i lost it..please pm back..
you have settled down in sg havent you? ;D ;D
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Here are the pix for my Denon TT re-plinthing project:
(http://farm5.static.flickr.com/4031/4333977893_34a4bef95c_o.jpg)
The original Plinth of the Denon 790.
(http://farm3.static.flickr.com/2743/4333977677_5c1e225be6_o.jpg)
The narra slab that I will be using (These are left-over from a kitchen renovation that my wife and I did for their family house in Batangas City). This was made using two slabs of narra glued together.
(http://farm5.static.flickr.com/4015/4334720524_0e70552538_o.jpg)
The dismantled Denon turntable and the glued up slab.
(http://farm3.static.flickr.com/2677/4409325487_a1ac23f984_o.jpg)
Dry fitting the turntable on the plinth.
(http://farm5.static.flickr.com/4029/4409325781_27414f1f1f_o.jpg)
Routing the recess for the armboard.
(http://farm3.static.flickr.com/2757/4410090746_9e56a6fa77_o.jpg)
(http://farm5.static.flickr.com/4012/4409351491_55c6e722f9_o.jpg)
Testing the assembly before finishing, it sounds so much better than the original plinth.
(http://farm3.static.flickr.com/2695/4409326095_60e2298ac6_o.jpg)
(http://farm5.static.flickr.com/4008/4410091142_e509559b16_o.jpg)
Mounting the armboard and the arm. With a couple of coats of wiping varnish.
(http://farm5.static.flickr.com/4009/4409326337_e9aeab2bb5_o.jpg)
Ready to spin some records after I install the platter and the cartridge.
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excellent craftsmanship!
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Hi alex,
Nice project! Getting betterer on woodworking lah! ;D
You're turntable has almost the same built as mine (DP-62L) kya lng wla sya tonearm! :(
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Here are the pix for my Denon TT re-plinthing project:
(http://farm5.static.flickr.com/4009/4409326337_e9aeab2bb5_o.jpg)
Ready to spin some records after I install the platter and the cartridge.
ganda naman.... ganyan gusto ko na maging yari sa gr1.2 ko :o :o :o
very nice, byutiful, congrats for such great re-plinthing ;D
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Ganda Sir alex, congrats!
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very nice alex, I do hope I can meet you guys in person someday... cheers
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ganda naman.... ganyan gusto ko na maging yari sa gr1.2 ko :o :o :o
very nice, byutiful, congrats for such great re-plinthing ;D
Source the wood, I can help you build it.
Sta Rosa road going to Tagayta have some wood sources.
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I had just finished reading the entir thread. what can I say... you do great work, I do hope I can make one for myself. btw, Bosch is hosting a tool seminar for a group that I belong to and I do the inviting ;D. if you are free, do join us so we can finally meet. details will be in the woodworking and tools thread. thanks
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Source the wood, I can help you build it.
Sta Rosa road going to Tagayta have some wood sources.
thanks... will look for an elegant looking wood
for soon to be your GR1.2 plinth project ;D ;D ;D
excited na. ::)
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Fr. Jim, if you are around sta. rosa, we can accompany you to look for your wood.....sabay session na rin. Long time na tayo di nag-uusap (Pinoy Aikido Club) ;D ;D ;D
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Hi timber,
Do the bosch guys offer power nailers?
Regards,
JoeyGS
I had just finished reading the entir thread. what can I say... you do great work, I do hope I can make one for myself. btw, Bosch is hosting a tool seminar for a group that I belong to and I do the inviting ;D. if you are free, do join us so we can finally meet. details will be in the woodworking and tools thread. thanks
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Hi timber,
Do the bosch guys offer power nailers?
Regards,
JoeyGS
to be honest, I haven't seen this locally, not even with the local Bosch suppliers. Bostich has great deals at amazon now. locally only Makita carries the good ones... that is as far as I know. ;D
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I had just finished reading the entir thread. what can I say... you do great work, I do hope I can make one for myself. btw, Bosch is hosting a tool seminar for a group that I belong to and I do the inviting ;D. if you are free, do join us so we can finally meet. details will be in the woodworking and tools thread. thanks
When is the Bosch tool seminar?
I have a lot of Bosch power tools, but honestly, am not happy with them.
One of these days, I would like to meet you, maybe I can go to Binondo, I need to get some tools. ;D
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When is the Bosch tool seminar?
I have a lot of Bosch power tools, but honestly, am not happy with them.
One of these days, I would like to meet you, maybe I can go to Binondo, I need to get some tools. ;D
alex,
I do hope you can join so we can meet ;D. the Bosch seminar is more on safety and since it was my idea, I asked them if it can focus on the woodworking side of tools. but I am certain that there will be some different applications on it. the link... http://www.pinoydvd.com/index.php?topic=108050.150 (http://www.pinoydvd.com/index.php?topic=108050.150)
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Nice creations Alex.