Tube Amp Archive

Cliff Jacks... Stinking Cliff Jacks... I hate Em... Always seem to wire them backwards!

Newly finished amp based on a Z-28 but using 5881 tubes... Sine wave shows up at speaker jack (8 ohm load or 8 ohm speaker attached) but no audio signal can be heard when speaker is plugged in. Output transformer reads: Primary: 411 ohms end to end / 205 ohms CT to each plate Secondary: 0.5 ohms Any...

The amp is not a PR but is similar. The pcb contains all circuitry for the entire amp

I can't take credit for this design but here's more of the trem circuit...

TT

I'm back, Finally got into the amp... Adding a bypass cap to R62 did the trick. The trem doesn't become audible until the Intensity pot is around 11 o'clock but it has plenty of depth as you turn it up and all the useful speed is there. I think I'm going to leave as is. Making further changes requir...

Thanks for those ideas sluckey, I was thinking about making R63 larger but I had previously changed R72 to 100k and was getting nasty distortion from Q6 output as a result. I'm thinking upping R63 may cause similar issues. I could raise it a small amount and see how it goes. I really like your idea ...

Hello guys, I have a Princeton Reverb type amp that originally had EL84 power tubes. It has a bias modulated tremolo circuit which works fine with the EL84's. Later, I changed the power tubes to 6V6's. Amp sounds great except now the tremolo is very weak. With the intensity cranked to 10 the tremolo...

your wet/dry mix stage is wired wrong.... look at a Twin Reverb schematic for the correct wiring

TT

I would like too, please and Thank You!

daveedburns@gmail.com

All my amps have bias adjustment for each tube... it's not a new thing. My last ODS 100W had a rotary switch and jacks to plug your volt meter into. The rotary switch allows you to toggle between power tubes. Overkill maybe but convenient!


TT

The JM Sig schematic posted on TAG shows the reverb being tapped before the 2nd stage. We are talking about the TwoRock amp, correct?

TT

Your reverb send could end up with too much gain since your feeding it after V1B (series) instead of before it (parallel) as Dumble does....

TT

FYI it looks like there's asbestos in the amp shown in these pics. If this material is in your amp you should seriously consider removing from the amp and properly disposing it.

TT

This is what I'm looking for....

This is what I'm looking for.....