Tube Amp Archive

Thanks for the ideas R.G.

Which cap would cause the Pop in this scheme?
C10 or C17 ?

Hi guys. Im having trouble with pop noise . what would be wrong here? As you can see there is dc on the relay switch comes from the PI grid. Is that the problem? I tried to put there different values of caps but pop noise still there and amplifier didnt sound the same as before in negative way. Is t...

Thanks a lot, im going to look closer on this subject.

Hi.Ive built half watt version. It sounds ok. By the way huge thanks for all of the information.
Whats the purpose of the diodes on the power tubes to ground? This Ive never seen on famous layouts and shemes.

Hello guys again. I’ve been working on power section of this project since 2 weeks. It finally sounds fantastic to me. But.. ive got a humming problem. Ive checked all of the filter caps and B+4-+5 components. Didnt help to eliminate. Source is where ? I dont really know. Sounds like 60cycle hum. Wh...

dorrisant wrote: ↑Sun Dec 27, 2020 10:33 pm EL84 pin #2 voltage?

There is no Dc voltage without tube. Shows me 0.235dc both tubes is that normal?

Without power and preamp tubes voltages on rectification tap is : 445 vac .
On El84 pin 9: 442vac pin 7 : 445 vac .
I Used Ceriatone’s Power layout, and rest Ron Worley’s.

Ok guys thanks for your helpful advises , i will write down all of my voltage readings without tubes here asap. Cheers.

They layout for the liverpool will work just fine, the only difference I see is the power section having 2 less tubes and 2 less components (don't need dual 220uF cathode caps and 130R cathode resistors, just one to tie the two together). The linked schematic to the 18W is different by quite a few ...

I would suggest to pull all of the tubes out and give us the voltages of the power tube sockets. Of particular interest is the voltage present on the #2 pins (bias voltage). This should be negative relative to the chassis. If you can list the voltages by the pins it would be helpful. Remember, with...

I also just merged the two identical posts in different sub-forums. Please don't do that... You'll get answers in whichever one you choose, but doing it in both isn't good etiquette on pretty much any forum. I put this one in the trainwreck discussion area since it's about a trainwreck variant. You...

Im sorry , i wish i could upload pics , and share with you guys but im working on my first built and im not on the greatest workmanship yet. But you guys will sure hear the sound. :) This project hopefully will be a full working prototype. I measured my rectified voltage once again now my multimeter...

Something is desperately wrong there, what’s your light bulb limiter showing? Twin TAG threads seems less than ideal, hopefully a mod can combine them. When standby on, lightbulb gets little brighter. My tubes are redplating too in high volume. When the volume in 12 o clock its ok. After 12 o clock...

Is there a solution and what can cause this problem? (if it is)

Thanks for help, 216 vdc now came down in 5 mins from 230 vdc .