Chinese EL34 amp to modify - Page 3 - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 5th February 2007, 05:32 PM   #21
Cobra2 is offline Cobra2  Norway
DIY !
diyAudio Member
 
Cobra2's Avatar
 
Join Date: Apr 2002
Location: Stavanger, Norway
Send a message via Skype™ to Cobra2
There are just one trimpot...

Arne K
__________________
Don't believe everything you think...
  Reply With Quote
Old 7th February 2007, 02:31 PM   #22
diyAudio Member
 
mississippi's Avatar
 
Join Date: Apr 2006
Location: holland
Here is the schematic diagram of this amplifier.
Attached Images
File Type: gif china_amp.gif (16.6 KB, 1516 views)
  Reply With Quote
Old 7th February 2007, 02:42 PM   #23
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Whenever you see output tubes on a cheap circuit board, and especially a board that's not highly perforated, you know you've got an amp destined for progeria.

As for the overall design, cough, cough, it's not exactly what I'd do...
__________________
And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berzerker mode; come at you like a whirling dervish, all fists and elbows.
  Reply With Quote
Old 7th February 2007, 02:55 PM   #24
Cobra2 is offline Cobra2  Norway
DIY !
diyAudio Member
 
Cobra2's Avatar
 
Join Date: Apr 2002
Location: Stavanger, Norway
Send a message via Skype™ to Cobra2
Default Holes are "free"

Can fix holes, both in pcb & chassi...

Next tip please!

Arne K

1000 x thanks to mississippi for making the great drawing...

__________________
Don't believe everything you think...
  Reply With Quote
Old 7th February 2007, 03:28 PM   #25
diyAudio Member
 
mississippi's Avatar
 
Join Date: Apr 2006
Location: holland
Youre welcom.
and for
Quote:
As for the overall design, cough, cough, it's not exactly what I'd do...
I'll agree!
  Reply With Quote
Old 7th February 2007, 04:02 PM   #26
diyAudio Member
 
Join Date: Jun 2004
Location: Atlanta, GA
I always like seperate transformers/rectifiers for low and high voltage.

You can keep the transformer you have now for high and just add another for the heater. Not real exspensive.
  Reply With Quote
Old 7th February 2007, 04:22 PM   #27
Cobra2 is offline Cobra2  Norway
DIY !
diyAudio Member
 
Cobra2's Avatar
 
Join Date: Apr 2002
Location: Stavanger, Norway
Send a message via Skype™ to Cobra2
I found this: http://www.arrakis.es/~igapop/russia...o%20use%20them
-and it show a very similar circuit...
How can this be improved?, (sorry, no space for an extra tube).

Arne K
__________________
Don't believe everything you think...
  Reply With Quote
Old 7th February 2007, 05:55 PM   #28
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
I guess you have to first define what you're after. A test bed for learning and experimentation? A long-term amp to use unmolested for listening? Different answers to those questions.
__________________
And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berzerker mode; come at you like a whirling dervish, all fists and elbows.
  Reply With Quote
Old 7th February 2007, 06:51 PM   #29
Cobra2 is offline Cobra2  Norway
DIY !
diyAudio Member
 
Cobra2's Avatar
 
Join Date: Apr 2002
Location: Stavanger, Norway
Send a message via Skype™ to Cobra2
Since it barely can make a pigs ear, I see no hope as a silk purse...
It will mostly be a test-bed,(training/learning), but first; it has to be usable.
As it it(was); it has no bass or punch...and had a glary top-end.
And not even close to a varm midrange.

Arne K
__________________
Don't believe everything you think...
  Reply With Quote
Old 7th February 2007, 07:06 PM   #30
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
I'd spend some time measuring the output transformers. If they've got the bandwidth and power handling to make a decent amp, then it could be worth stripping everything else out and starting with that as a base. If they don't, just reconnect them, sell the amp, and use the money to buy some decent iron.
__________________
And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berzerker mode; come at you like a whirling dervish, all fists and elbows.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Another Chinese Rip-off? Bakmeel Pass Labs 3 1st February 2009 08:10 AM
Chinese FRs dublin78 Full Range 1 26th November 2008 02:05 AM
Chinese GC iamwiam Chip Amps 31 20th March 2005 08:22 AM
Chinese new 845 Yu Tubes / Valves 27 13th February 2005 08:16 AM


New To Site? Need Help?

All times are GMT. The time now is 12:40 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2