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Home Theater => Audio => Tubes => Topic started by: rochie on Aug 03, 2016 at 02:27 PM

Title: New tube preamp and tube amp build
Post by: rochie on Aug 03, 2016 at 02:27 PM
Ill be starting my tube preamp and tube amp build.
got the kits from a friend from China.
test equipments also came from him :D :D :D

(http://i1282.photobucket.com/albums/a533/r0ch13/microMsg.1469536776849_zps1ctuasef.jpg) (http://s1282.photobucket.com/user/r0ch13/media/microMsg.1469536776849_zps1ctuasef.jpg.html)

(http://i1282.photobucket.com/albums/a533/r0ch13/IMG-1465129708229-V_zps2q9sp9hm.jpg) (http://s1282.photobucket.com/user/r0ch13/media/IMG-1465129708229-V_zps2q9sp9hm.jpg.html)
(http://i1282.photobucket.com/albums/a533/r0ch13/P_20160605_171000_zpsnbgxkrt3.jpg) (http://s1282.photobucket.com/user/r0ch13/media/P_20160605_171000_zpsnbgxkrt3.jpg.html)
Title: Re: New tube preamp and tube amp build
Post by: tony on Aug 11, 2016 at 12:40 PM
rochie, that diy line amp has two big holes and two small ones aside from the rectifier...
so a phono stage and 6sn7 line stage  ala vacuum tube valley can be made....http://www.tiffe.de/roehren/VTV/VTV11.pdf
phono stage can be passive type from  the rca manual...
https://www.google.com.ph/search?q=phono+stage+can+be+passive+type+from+the+rca+manual.&oq=phono+stage+can+be+passive+type+from++the+rca+manual.&aqs=chrome..69i57&sourceid=chrome&ie=UTF-8
Title: Re: New tube preamp and tube amp build
Post by: rochie on Aug 11, 2016 at 05:01 PM
rochie, that diy line amp has two big holes and two small ones aside from the rectifier...
so a phono stage and 6sn7 line stage  ala vacuum tube valley can be made....http://www.tiffe.de/roehren/VTV/VTV11.pdf
phono stage can be passive type from  the rca manual...
https://www.google.com.ph/search?q=phono+stage+can+be+passive+type+from+the+rca+manual.&oq=phono+stage+can+be+passive+type+from++the+rca+manual.&aqs=chrome..69i57&sourceid=chrome&ie=UTF-8

cool, thanks Sir Tony for the info.will build the first kit as is and then will build another one with phono stage as recommended. sabay kami ni Ralph mag build hehehehe meron din sya tube preamp kit.
Title: Re: New tube preamp and tube amp build
Post by: tony on Aug 11, 2016 at 07:26 PM
cool, thanks Sir Tony for the info.will build the first kit as is and then will build another one with phono stage as recommended. sabay kami ni Ralph mag build hehehehe meron din sya tube preamp kit.

the preamp was a variation of the marantz 7 topology using the 6V6 and 6au6 pentodes..
first implemented with the 12ax7's...
and uses lots of global negative feedback, why so many audiophools like them is an enigma....
Title: Re: New tube preamp and tube amp build
Post by: Abad Santos 7 on Aug 15, 2016 at 12:36 PM
Sir Special Request.. baka pede pashow how to test this amp....(of course when finished already....)

Cheers.
Title: Re: New tube preamp and tube amp build
Post by: tony on Aug 15, 2016 at 12:39 PM
Sir Special Request.. baka pede pashow how to test this amp....(of course when finished already....)

Cheers.

i do it in stages, first you wire up the filaments, then power up and see that all tubes are lit....
then the psu, then on to the output tube and finaly the input tube, this is the sequence that i follow...
do not do everything at once, do it incrementaly, per tube and double check....
Title: Re: New tube preamp and tube amp build
Post by: rochie on Aug 15, 2016 at 01:22 PM
i do it in stages, first you wire up the filaments, then power up and see that all tubes are lit....
then the psu, then on to the output tube and finaly the input tube, this is the sequence that i follow...
do not do everything at once, do it incrementaly, per tube and double check....
actually yan ang plano ko Sir Tony,
filament muna para makita kung mag glow mga tubes.
pero unahin ko muna yung preamp kit para mas madali.
nakabit ko na nung weekend yung mga mechanical. will try to wire the filament/heater on my rest day

(https://scontent.fmnl4-5.fna.fbcdn.net/v/t1.0-0/p526x296/13920684_10154419266541563_2889300002708228705_n.jpg?oh=3e685f2533770b6c0365804622af5b1e&oe=58188DF6)
Title: Re: New tube preamp and tube amp build
Post by: Abad Santos 7 on Aug 17, 2016 at 09:43 AM
i do it in stages, first you wire up the filaments, then power up and see that all tubes are lit....
then the psu, then on to the output tube and finaly the input tube, this is the sequence that i follow...
do not do everything at once, do it incrementaly, per tube and double check....

Noted.  This is seems logical for easy trouble shooting and safety.
Title: Re: New tube preamp and tube amp build
Post by: tony on Aug 17, 2016 at 09:50 AM
Noted.  This is seems logical for easy trouble shooting and safety.

indeed, getting then done in stages is the best way....
Title: Re: New tube preamp and tube amp build
Post by: rochie on Aug 17, 2016 at 10:35 AM
indeed, getting then done in stages is the best way....
mas madali din mag troubleshoot.
Title: Re: New tube preamp and tube amp build
Post by: Abad Santos 7 on Aug 19, 2016 at 02:12 PM
indeed, getting then done in stages is the best way....

With paying special attention on capacitor discharging.... with or without the bleeder....
Title: Re: New tube preamp and tube amp build
Post by: tony on Aug 19, 2016 at 05:14 PM
bleeders are imperative for safety, i use at least a 3 watt 1.5M resistor...
Title: Re: New tube preamp and tube amp build
Post by: fantom_mayonaise on Feb 02, 2017 at 03:57 PM
Build Pics  :)

Painted the stainless chassis with hammerfinish

(http://img.photobucket.com/albums/v227/rough512/Tube%20Preamp%202/E53ADF8B-513B-4C15-A150-31BE7BD45381_zps1zzkqwbg.jpg)
Title: Re: New tube preamp and tube amp build
Post by: fantom_mayonaise on Feb 02, 2017 at 03:59 PM
Point to point wiring of components. I used a bus wire for ground, running from the power supplu up to the volume control.

(http://img.photobucket.com/albums/v227/rough512/Tube%20Preamp%202/B7CEB52C-7E83-42F9-85CF-D8D5A6816DD6_zpsbn9s2d1w.jpg)
Title: Re: New tube preamp and tube amp build
Post by: fantom_mayonaise on Feb 02, 2017 at 04:05 PM


(http://img.photobucket.com/albums/v227/rough512/Tube%20Preamp%202/B7CEB52C-7E83-42F9-85CF-D8D5A6816DD6_zpsbn9s2d1w.jpg)
Title: Re: New tube preamp and tube amp build
Post by: fantom_mayonaise on Feb 02, 2017 at 04:10 PM
Final zipties

(http://img.photobucket.com/albums/v227/rough512/Tube%20Preamp%202/343600C8-54D6-4258-A7DD-DC347BB69169_zpsb00kwgif.jpg)
Title: Re: New tube preamp and tube amp build
Post by: fantom_mayonaise on Feb 02, 2017 at 04:13 PM
Done....


Almost.  ;D ;D

(http://img.photobucket.com/albums/v227/rough512/Tube%20Preamp%202/BF11A74C-7317-4DF4-B9B7-6AC39F2CF498_zpsir0lyjex.jpg)


I need a muting circuit for this preamp. During power-on, it activates my amp's DC protect.
Title: Re: New tube preamp and tube amp build
Post by: rochie on Feb 02, 2017 at 04:16 PM
cool.
Title: Re: New tube preamp and tube amp build
Post by: fantom_mayonaise on Feb 02, 2017 at 04:21 PM
First time ko makagamit ng heater wires na may center tap. Yung sa picture sa taas, di ko sya naikonek sa PS ground, kaya yung initial power-on, nakilala ko si Major Hum. Ang kulit na at malakas ang dating nya. Pero napalayas ko rin sya after ko makonek yung center-tab sa PS Ground.

Okay yung tunog nya maliban lang dun sa power-on DC surge.
Title: Re: New tube preamp and tube amp build
Post by: tony on Feb 02, 2017 at 04:52 PM
look at the heater to cathode voltage specs on the datasheets
of tubes you are using, this is very important,
if there is a chance that this will be exceeded,
then dc voltage lifting filaments is a
good way to eliminate hum and or buzzz....https://www.google.com.ph/search?q=then+dc+voltage+lifting+filaments&rlz=1C1CHBF_enPH711PH711&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj75-TZhPHRAhXBEpQKHZt_CkkQ_AUICCgB&biw=1366&bih=648
Title: Re: New tube preamp and tube amp build
Post by: rochie on Feb 02, 2017 at 04:54 PM
First time ko makagamit ng heater wires na may center tap. Yung sa picture sa taas, di ko sya naikonek sa PS ground, kaya yung initial power-on, nakilala ko si Major Hum. Ang kulit na at malakas ang dating nya. Pero napalayas ko rin sya after ko makonek yung center-tab sa PS Ground.

Okay yung tunog nya maliban lang dun sa power-on DC surge.

baka kailangan ng delay sa power on ng amp kung iisa lang ang power switch? alam ko meron ako ganon na nakatago,kailangn lang palitan value ng capacitor kung gaano katagl yung delay na gusto mo.
Title: Re: New tube preamp and tube amp build
Post by: tony on Feb 03, 2017 at 10:55 AM
Quote
Okay yung tunog nya maliban lang dun sa power-on DC surge.

you can insert higher impedances on the psu....
tubes are such low current consumers that even high resistance
in the psu will not harm operation....

also, the output cap of that line amp must have a resistor from
output to ground, 100 to 220k is a good one to use...
Title: Re: New tube preamp and tube amp build
Post by: jravacio on Feb 07, 2017 at 01:59 PM
@fantom_mayonaise nandito lng pala kayo... quite a while since I saw you at elab... great work :)
Title: Re: New tube preamp and tube amp build
Post by: tony on Feb 07, 2017 at 03:50 PM
John, nasa abroad sya sa pagkakaalam ko.....
Title: Re: New tube preamp and tube amp build
Post by: fantom_mayonaise on Feb 12, 2017 at 11:58 PM
Sir JohnR :

Kumusta po. Sir Tony andito lang po ako sa Makati. Dumalaw lang sa sister ko last year.


Title: Re: New tube preamp and tube amp build
Post by: tony on Feb 13, 2017 at 07:29 AM
fanthom, post ka rin dito: http://www.elab.ph/forum/index.php?topic=34991.msg909848#new