PinoyDVD: The Pinoy Digital Video & Devices Community
Home Theater => Audio => Tubes => Topic started by: silent_loud21 on May 06, 2018 at 03:16 PM
-
baka may naka subok na tempting... :) pasok na pasok sa budget
https://www.lazada.com.ph/products/audio-mini-6j1-valve-vacuum-tube-pre-amplifier-stereo-hifi-buffer-preamp-dc12v-intl-i161712137-s197805690.html?spm=a2o4l.searchlist.list.9.61032ec6xwXmjJ&search=1 (https://www.lazada.com.ph/products/audio-mini-6j1-valve-vacuum-tube-pre-amplifier-stereo-hifi-buffer-preamp-dc12v-intl-i161712137-s197805690.html?spm=a2o4l.searchlist.list.9.61032ec6xwXmjJ&search=1)
user review from lazada..
."Tube amps have been a popular audiophile gismo and became my life’s wish list the first time I heard it play on an audio shop I visited many years back.
But the jaw-dropping price kept it stuck on my dreams. This cheap brand exceeded my expectation when I paired it with my Onkyo stereo amp driving my current hungry Platinum Solo speaker.
I love listening to the warmth and subtle detail of this tube pre-amp even on a low volume. I finally found the missing link to my audiophile quest, in less the price."
-
12V pwede car audio 😁
-
yes why not? that is basically a buffer with volume control,
not sure though about gain structure, have to see under the hood..
but again, at that price, a winner na.....:D
the caveat though is if the tube that came with it is microphonic,
but at 1800 pesos, who cares?
tube rolling hints.....https://www.aliexpress.com/item/New-American-GE-5654-tube-super-sound-substitution-6J1-6-m-1-6AK5-EF95-exact-matching/32798750888.html
-
^ panalo to at its pricepoint. may voucher pa. what is a microphonic tube sir tony?
-
can this be used as an electric guitar preamp kung babaguhin input and output jacks from rca to 6.3mm mono connector? tia
-
^ panalo to at its pricepoint. may voucher pa. what is a microphonic tube sir tony?
hissing, and making noise when the glass is tapped even lightly...
-
this is reason the local diy scene is dying....https://www.ebay.com/itm/6J1-Valve-Pre-amp-Dual-Channel-Tube-Preamp-Preamplifier-Board-PCB-new-hot-/281902308485?var=&hash=item41a2afdc85:m:mKl8CtIIvJJDjo4lXhztSbQ
-
can this be used as an electric guitar preamp kung babaguhin input and output jacks from rca to 6.3mm mono connector? tia
not sure that it has enough gain kung guitar pickup ang input, you will need at least 60db, the most we can expect here is 20db or less...
-
this is reason the local diy scene is dying....https://www.ebay.com/itm/6J1-Valve-Pre-amp-Dual-Channel-Tube-Preamp-Preamplifier-Board-PCB-new-hot-/281902308485?var=&hash=item41a2afdc85:m:mKl8CtIIvJJDjo4lXhztSbQ
I beg to disagree. Kung ang goal lang is magkaroon then why not. Pero sa tunog, I won't expect much.
-
yes why not? that is basically a buffer with volume control,
not sure though about gain structure, have to see under the hood..
but again, at that price, a winner na.....:D
the caveat though is if the tube that came with it is microphonic,
but at 1800 pesos, who cares?
tube rolling hints.....https://www.aliexpress.com/item/New-American-GE-5654-tube-super-sound-substitution-6J1-6-m-1-6AK5-EF95-exact-matching/32798750888.html
If that is indeed a buffer, usually configured as a parallel cathode follower then gain is automatically less than 1. Gain structure doesn't exist in a buffer and if that is the case then palamuti lang yan whose sole benefit in using is driving very long cables.
-
not sure that it has enough gain kung guitar pickup ang input, you will need at least 60db, the most we can expect here is 20db or less...
thanks, sir
-
thanks, sir
yes and as jojod said, just about 0db of gain...
-
i spoke to soon....
found the schematics at diyaudio.com...
this preamp has gain after all, Av = 4700/(rk + 200) ohms, if rk = 200 ohms, then voltage gain is 11.75 or about 21.4db, i predicted 20db which is typical for most line preamps... 8)
(https://i.imgur.com/MPtiKE5.png)
-
X10d psu.
-
my 6bc4 used the same topology, B+ of about 140 volts....this amp can use a better psu....
-
Speaking of tube amps available from Lazada how about this?:
(https://ph-live.slatic.net/v2/resize/products/S-6885-40590be6547bb5f811bc753dd69481b3.jpg)
https://www.lazada.com.ph/products/220v-350w-bluetooth-40-hi-fi-21-tube-amplifier-stereo-power-amp-usb-mic-remote-intl-i171831671-s214702233.html?spm=a2o4l.searchlist.list.48.3c485639vxdPsu&search=1 (https://www.lazada.com.ph/products/220v-350w-bluetooth-40-hi-fi-21-tube-amplifier-stereo-power-amp-usb-mic-remote-intl-i171831671-s214702233.html?spm=a2o4l.searchlist.list.48.3c485639vxdPsu&search=1)
Is this better than say a Dared MP5? Or are there better alternatives in a similar price point?
-
same hybrids, tubes for line amps ang ss to drive speakers....
i can not make the same for that look and for that price....
-
nasubukan ko to. buti nalang may lazada return.
may channel imbalance yun sample na nakuha ko. tapos ang pangit tignan sa personal nung silver. go for black, and hopefully sana walang channel imbalance yung makuha nyo. it was nice sounding. Nabawasan ng details compared to volume control of my NAD M51 DAC pero mas naging palpable yung mga boses ng onti.
-
Any tips or mods so far with the 6j1? I bought the board with tubes without the casing at Lazada. Enjoying it!
-
live with it for while, if your are enjoying it, why change it?
-
https://www.lazada.com.ph/products/6j1-hifi-stereo-electronic-tube-preamplifier-board-finished-preamp-amplifer-module-intl-i170330967-s212564470.html?spm=a2o4l.searchlist.list.7.54b6402d2JDnqY&search=1
Can anyone tell me if this is DHT?
-
DHT, direct heated tube? nah, this is a 6ak5 pentode wired as triode and is not a dht....
the 3A5 is a DHT, the tube with the highest mu of its class...
the CX01m CX26 are examples of DHT's...
can you tell me why you ask?
-
No, nothing in particular, just curious ::) When the volume control of this preamp is cranked to the end, it distorts , so one has to keep it at a lower volume maybe only up a quarter. I'm am just using a wall wart I found in the garage at the moment since it did not come with one.
-
"this amp can use a better psu...." how do we propose to do this, sir?
-
No, nothing in particular, just curious ::) When the volume control of this preamp is cranked to the end, it distorts , so one has to keep it at a lower volume maybe only up a quarter. I'm am just using a wall wart I found in the garage at the moment since it did not come with one.
that is called clipping distortion.....laws of physics at work...
-
"this amp can use a better psu...." how do we propose to do this, sir?
did i wet your appetite?
a better psu will lead to a better design.....
-
https://www.lazada.com.ph/products/piso-net-power-transformer-220-12v-i122747237-s127866885.html?spm=a2o4l.searchlist.list.1.2fa2a186lfBoFl&search=1
Will this do?
-
i have owned this.... mine came with stock PSU.
upgraded the tubes to this, Voskhod 6J1P https://www.amazon.com/Voskhod-6J1P-EV-6ZH1P-EV-Matched-Pair/dp/B071H78DHZ (https://www.amazon.com/Voskhod-6J1P-EV-6ZH1P-EV-Matched-Pair/dp/B071H78DHZ)
resulted in a noticeable improvements on SQ.
-
https://www.lazada.com.ph/products/piso-net-power-transformer-220-12v-i122747237-s127866885.html?spm=a2o4l.searchlist.list.1.2fa2a186lfBoFl&search=1
Will this do?
yes, but locally available 12v traffos from deeco will also do...
-
Changed the wall wart to a 12volt AC 1A transformer (Deeco=P180) already. No more distortion as well as lots more volume. For the sound quality I think, lesser foot tapping, lesser involvement, lesser teary-eyedness, I don't know why?
-
Changed the wall wart to a 12volt AC 1A transformer (Deeco=P180) already. No more distortion as well as lots more volume. For the sound quality I think, lesser foot tapping, lesser involvement, lesser teary-eyedness, I don't know why?
a 13 volt 1 amp traffo will be better imho, but you are probably hitting it already...
try different types of 6ak5's for tube rolling, look for Gerry Sta Maria, he can help you with tubes...09217430558
-
No more distortion as well as lots more volume. For the sound quality I think, lesser foot tapping, lesser involvement, lesser teary-eyedness, I don't know why?
kulang sa lambing? too clinical? sa chip based amps yan din observation ko. ang linis, great sounding pero parang walang character, "lesser involvement" as you said. same question, why? why cant the china products now replicate even a fraction of japan made amps' character? if character is the word.
-
kulang sa lambing? too clinical? sa chip based amps yan din observation ko. ang linis, great sounding pero parang walang character, "lesser involvement" as you said. same question, why? why cant the china products now replicate even a fraction of japan made amps' character? if character is the word.
why? because to goal of the design is to sell cheap...
with those kinds of voltages? what to expect? tubes are run with voltages much higher than what was designed into that...
the 6j1/6ak5 unlike the 6dj8 are not that high transconductance...
i takes 4 to 5 plates to approach 6dj8 levels....
plate resistance is likewise high so output swing is low...
but, but, but, at 1800 pesos who is to complain? not me... :D
-
i got one of these the other day. hooked it up along the signal chain, the immediate effect i heard generally is mild increase in middle frequencies - a nice change if i may say... no humming, the casing and physical build quality is ok, and it worked as advertised... for such an inexpensive tube gear! ;D
others in the international audio forums advise to try replacing the stock tubes with GE5654W for maximum/optimized tube effect daw... but at the moment i-enjoy lang muna yung stock unit ;D
(P.S. my unit is connected to a linear regulated power supply).
-
a 13 volt 1 amp traffo will be better imho, but you are probably hitting it already...
try different types of 6ak5's for tube rolling, look for Gerry Sta Maria, he can help you with tubes...09217430558
Thanks, sir, but no reply from mr.gerry yet. And yes you're right, I tested it with a multitester and it says 13.36v AC.
-
Depende kung magkano amp na binebenta. Mga galing Tsina karamihan may pagka mura dahil mahirap kasi magbenta ng mahal lalo kung hindi kilala ang tatak. Pero meron din maganda talaga tumunog na may character din.
kulang sa lambing? too clinical? sa chip based amps yan din observation ko. ang linis, great sounding pero parang walang character, "lesser involvement" as you said. same question, why? why cant the china products now replicate even a fraction of japan made amps' character? if character is the word.
-
Thanks, sir, but no reply from mr.gerry yet. And yes you're right, I tested it with a multitester and it says 13.36v AC.
Gerry is also on facebook, you can catch him there also....https://www.facebook.com/gerry.stamaria.9
-
Thanks! :) Do you think there is any slim chance changing the tubes could make it kinda sweet sounding again, sir? I already miss Eydie Gorme singing Sabor a mi ^-^
-
Thanks! :) Do you think there is any slim chance changing the tubes could make it kinda sweet sounding again, sir? I already miss Eydie Gorme singing Sabor a mi ^-^
don't pin your hopes too high....remember this is an el cheapo amp...
btw, i can lend you a pairs ot the 6ak5's...
-
share ko lang po ... I upgraded the tubes to NOS GE JAN 5654W (General Electric Joint ArmyNavy military spec/grade) I ordered from Riverstone Audio in USA...
so I removed the stock 6J1 chinese made tubes...pagsalpak ko sa FX audio preamp,,, ayun o! me improvement nga...mas lumutang ang instruments, voices,mas madetalye... parang mas improve ng konti ang bass .... halos same soundstage... overall mas "tube sounding" ito vs. using the stock tubes...
an inexpensive way to get "tube sound magic" :)
(used with a class D amp and famous diatone alnico fullrangers )
-
i have ordered mine and expecting delivery soon....
-
share ko lang po ... I upgraded the tubes to NOS GE JAN 5654W (General Electric Joint ArmyNavy military spec/grade) I ordered from Riverstone Audio in USA...
so I removed the stock 6J1 chinese made tubes...pagsalpak ko sa FX audio preamp,,, ayun o! me improvement nga...mas lumutang ang instruments, voices,mas madetalye... parang mas improve ng konti ang bass .... halos same soundstage... overall mas "tube sounding" ito vs. using the stock tubes...
an inexpensive way to get "tube sound magic" :)
(used with a class D amp and famous diatone alnico fullrangers )
Bro how much is that replacement tube? is this 7pins also?
-
Bro how much is that replacement tube? is this 7pins also?
Bro Php2,319 binayaran ko... thru Galleon Philippines,,, cash on delivery.... pag sa lazada mas mahal yata ng 1k pesos ... yes its 7 pins... all they say in the international audio forums are true,,, that these GE tubes greatly improve the performance of this el cheapo tube preamp... I'm one happy user :-)
-
^meron ako nyan 1k for a pair....
6j1 preamp, i got mine for 765 pesos from lazada, and for power supply, i have 12 volt/1amp walwart, a JRC power brick from my old old old cellphone in the 90's....
(https://scontent.fmnl2-1.fna.fbcdn.net/v/t1.0-9/36926074_1940347352653556_8980851455741132800_n.jpg?_nc_cat=0&_nc_eui2=AeGRk88Dm8AGOHsRFBCFc8W4YhYKbY1nUOnZfHAgiKt68h50nrtsez79QvMe3aubWHhPwAahC2w26XcIfbV96X3JXLcYsJBNuuB9y9-XebggPQ&oh=b869b48093949139200a0ee174378fff&oe=5BE9BF8B)
-
12VAC?
-
Anyone tried the version with Bass and Treble controls ?
https://www.lazada.com.ph/products/new-fx-audio-tube-03-mini-bile-6j1-preamp-tube-amplifier-buffer-hifi-audio-preamplifier-treble-bass-adjustment-pre-amps-dc12v-intl-i170645089-s213077475.html?spm=a2o4l.searchlist.list.1.2d941ded7VpP4r&search=1
-
^
I did. Walang detent para flat yung equalization. Very sensitive yung control nung bass and treble controls so onting galaw lang may difference agad.
Yung GE na 5654W tubes ba may difference yung may green print na version dun sa white print lang?
-
^meron ako nyan 1k for a pair....
6j1 preamp, i got mine for 765 pesos from lazada, and for power supply, i have 12 volt/1amp walwart, a JRC power brick from my old old old cellphone in the 90's....
(https://scontent.fmnl2-1.fna.fbcdn.net/v/t1.0-9/36926074_1940347352653556_8980851455741132800_n.jpg?_nc_cat=0&_nc_eui2=AeGRk88Dm8AGOHsRFBCFc8W4YhYKbY1nUOnZfHAgiKt68h50nrtsez79QvMe3aubWHhPwAahC2w26XcIfbV96X3JXLcYsJBNuuB9y9-XebggPQ&oh=b869b48093949139200a0ee174378fff&oe=5BE9BF8B)
Kuya just sell it to me the replacement tube? Thanks
-
Kuya just sell it to me the replacement tube? Thanks
pm me your shipping details and i will send you a pair...any preference? american or japanese? these are 6ak5's...you can pay thru lbc...antonio tecson jr.
-
tubes shipped yesterday morning, you should be able to pick it up today...
-
yup ill check it out after office hours. Salamat po!
-
Finally ordered the one with the bass and treble controls. Will use this for my 2 channel HT system.
-
I got something like that in the mail.
I should be powered by ac 12v 2 amp atleast for what it said.
It is only 450 pesos or around 8 usd.
-
^it must be selling like hotcakes then Joffkevsky...
-
^
I did. Walang detent para flat yung equalization. Very sensitive yung control nung bass and treble controls so onting galaw lang may difference agad.
Yung GE na 5654W tubes ba may difference yung may green print na version dun sa white print lang?
i got the green print version from Riverstone Audio.
i don't know about the white printed ones...
but the green ones i think are the ones made for military grade...
the value add offered by Riverstone Audio is that they pre-selected matched pairs good for audio applications...
-
Been listening to this inexpensive pre-amp for the past couple of days and it is very good for the price. My initial plan was to use this for my 2 channel HT system. The pre-amp got "promoted" and it is now on 2 channel audio duties. It is now mated to a 205 WPC Parasound power amp driving Acarian Alon IV loudspeakers.
The only negative thing for me was that the potentiometer was too sensitive, I needed to reduce my power amp gain by 40 percent otherwise my max volume would be at the 9'oClock setting, with the reduced gain my b volume control can reach up to 12.
-
this amp can be hacked for lower gains....if desired...just two resistors in parallel with the plate load resistors.....R15/R20, just solder in 4.7k metal film resistors to the existing ones, or replace them with 2.7k resistors lowers the gain of this line amp..
(https://i.imgur.com/MPtiKE5.png)
-
Thanks for the TIP, when I get enough courage, will operate on this amp :)
this amp can be hacked for lower gains....if desired...just two resistors in parallel with the plate load resistors.....R15/R20, just solder in 4.7k metal film resistors to the existing ones, or replace them with 2.7k resistors lowers the gain of this line amp..
(https://i.imgur.com/MPtiKE5.png)
-
Had a positive user experience with the audio mini 6J1 tube preamp - mine is FX Audio Tube 01 I replaced with GE JAN 5654W tubes from Riverstone Audio.
Today i saw in Lazada they offer FX Audio Tube P1... single ended tube amplifier with 2watt+2watt power output.... hmmmm... ;D
https://www.lazada.com.ph/products/fx-audio-tube-p1-6j1-6p1-hifi-mcu-single-ended-classic-a-desktop-power-tube-amplifier-headphone-amplifier-rcaphono-input-i261737726-s361530932.html?spm=a2o4l.searchlist.list.45.fcae5639q8e9dF&search=1
meron na ba sa inyo mga Sir naka-try nito? I'd like to know your feedbacks/reviews sana... if ever, i'm planning to pair this with high sensitive fullrange speaker (for listening to mostly jazz music)...
-
What is the sensitivity of your speakers ?
Had a positive user experience with the audio mini 6J1 tube preamp - mine is FX Audio Tube 01 I replaced with GE JAN 5654W tubes from Riverstone Audio.
Today i saw in Lazada they offer FX Audio Tube P1... single ended tube amplifier with 2watt+2watt power output.... hmmmm... ;D
https://www.lazada.com.ph/products/fx-audio-tube-p1-6j1-6p1-hifi-mcu-single-ended-classic-a-desktop-power-tube-amplifier-headphone-amplifier-rcaphono-input-i261737726-s361530932.html?spm=a2o4l.searchlist.list.45.fcae5639q8e9dF&search=1
meron na ba sa inyo mga Sir naka-try nito? I'd like to know your feedbacks/reviews sana... if ever, i'm planning to pair this with high sensitive fullrange speaker (for listening to mostly jazz music)...
-
What is the sensitivity of your speakers ?
rated 93db ... the other pair rated at 96db
-
That should work...
The only question left is will it sound good on the 2 watt tube amp
rated 93db ... the other pair rated at 96db
-
https://www.diyaudio.com/forums/tubes-valves/309876-6j1-china-preamp-3.html#post5664882
-
After getting NOS GE 5654W tubes, I strongly suggest that you upgrade the op amps too. A pair of LM4562 work very nicely after the required burn in and a couple of weeks of use. Have a couple of other op amps on the way too (MUSES 8920 and SX52). I'm using a KGUSS T3 BILE 6J1 preamp which I got for P1650.
-
Hi sir Teta,
Very interesting upgrade there. Do you think it (OP amp) will also work/fit with the original poster's item (FX Audio Tube-01)?
And where do you source the said OP amps?
Thanks!
-
i have those opamps in my bin, but for the particular 6J1 featured here, no amp amps were used....btw, i also have the western electric 403 tube equivalent of the 6j1/5654 pentodes....
-
Hi sir Teta,
Very interesting upgrade there. Do you think it (OP amp) will also work/fit with the original poster's item (FX Audio Tube-01)?
And where do you source the said OP amps?
Thanks!
I chose the Kguss T3 Nike 6j1 preamp since the internal components seem to be of good quality. I get my op amps from Lazada, Shopee, or Ebay. So far, my best sounding op amps are a dual modded OPA627AU (Audio Jade version) and the LM4562. I have a Muses 8920 on the way too.
-
opa2134 is also a nice opamp to try...https://pdf1.alldatasheet.com/datasheet-pdf/view/603025/TI1/OPA2134.html
-
Where to get upgrade tubes for these? I'll purchase one soon.
-
Where to get upgrade tubes for these? I'll purchase one soon.
western electric version of the 6ak5...https://www.thetubestore.com/western-electric-403-a
-
Thanks sir Tony.
Help please.i've replaced my opamps to opa2134 and tubes to ge5654. After the changes the volume output significantly reduced.it's like 50% of the previous output. I've returned the original opamps and tubes suspecting that the new opamps and tubes were the culprit but it's still the same.
What to do now?😁
-
please post pictures, what preamp is that?, the 6j1 did not use op amp afaik...what psu are you using? it should be 12vac at least...
-
please post pictures, what preamp is that?, the 6j1 did not use op amp afaik...what psu are you using? it should be 12vac at least...
The fxaudio tube03 sir. i'm using the stock power supply.12v
-
ah, that one with the tone control, so that was what the opamps were for....have your unit checked by markrenz our resident repair tech......
-
this amp can be hacked for lower gains....if desired...just two resistors in parallel with the plate load resistors.....R15/R20, just solder in 4.7k metal film resistors to the existing ones, or replace them with 2.7k resistors lowers the gain of this line amp..
(https://i.imgur.com/MPtiKE5.png)
Can i remove some resistors to increase the gain?😁
-
Can i remove some resistors to increase the gain?😁
if you increase the gain, you get more distortion, is this what you want? reducing the plate load resistor decreased gain but increased bandwidth and lowered output impedance...
-
btw, i have about 10 pairs, 5654's and hitachi 6ak5, the 5654 is 1000 per pair and the hitachi's are 1500 a pair....
-
Can convert this into a head phone amp for small in ear headphones by connecting a female headphone jack inputs into the RCA outputs ?
headphones specs
Sensitivity: 112dB
Impedance: 25Ω
-
^i doubt it, high output impedance unless you are using earphones with greater than 2k ohm, perhaps a matching transformer will work better...
-
My FX Audio Mini 6j1 tube preamp is now two year old. Lately i noticed popping sound is outputted by the preamp to the amplifier, ano po kaya ang dahilan?
-
ecaps drying out can be culprit...
-
ecaps drying out can be culprit...
Thanks sir Tony. Time to visit a friend.
-
My FX Audio Mini 6j1 tube preamp is now two year old. Lately i noticed popping sound is outputted by the preamp to the amplifier, ano po kaya ang dahilan?
na try mo na ba i-pull out the tubes and re insert baka me maluwag lang o dumi sa fitment between tube pins and tube socket
-
na try mo na ba i-pull out the tubes and re insert baka me maluwag lang o dumi sa fitment between tube pins and tube socket
yes, this can also be a cause china sockets gets tarnished more easily, kahit pa ceramic sya, yung metal na ginamit parang metal ng maling...... :D
-
agree with tony about the caps but 2 years is a not really a long time imo so i think potentiometer/vol knob might also need replacing
-
agree with tony about the caps but 2 years is a not really a long time imo so i think potentiometer/vol knob might also need replacing
onsidering the quality of china goods, that is not surprising...
-
onsidering the quality of china goods, that is not surprising...
Actually had to rethink after posting, Chongx comes to mind. lol
-
buhayin natin ang thread na to... i bought a Miniwatt 2013 SET tube amplifier 3 watts per channel, bought from Shoppee many months ago... after completing the burn in process of 100 hours (as per recommendation) - ayun nag open up na nga ang tunog!.... pero nakulangan ako sa bass.... so I tried to source an equally inexpensive NFX Audio preamp (with bass & treble controls)... these I then connected to my hi efficiency fullrange single driver speakers (either fostex or diatone).... boom! full bodied sound! i can't believe 3 watts is powerful enough for my room setup/needs. ganda talaga tube sound! paired with mentioned speakers. sila talaga magka match.... in my experience di na kelangan to shell out large amount of money to enjoy music thru tubes ;D