Tube Amp Archive

It's a bit of a mess, due to me trying various things to fix it, but here are some gutshots.

Hey. I built an amp a bit similar to the 65 amps soho. But I have some issues with it: If I use my strat neck pickup (in particular) and max the volume and treble, I get a squeel. This is only WITHOUT the bump circuit or the +/- boost engaged. I'm assuming that I got oscilliations somewhere. I have ...

Awesome, thankyou
Heh - it's your time and your decision - any impatience on my part is irrelevant

Thanks for the continued information. Point one, I think the schematic shows the cap as going from signal to ground, not ground to chassis? But I could be reading it wrong. I think you may have misunderstood me on point 5 - the values of the cathode resistor and cap.... In the schematic you have set...

Thanks for updating the schematic, and adding voltages - that's awesome! I got questions :-) 1) the blue thingimabob on the input.... text on it says RIE / 104M, so I might also assume .1µF, but can that be true? wouldnt that shunt way too much of the signal to ground?? 2) I do see there's two 68k's...

yeah that makes sense. How about the whole bump-circuit? I cant exactly make it out in the pictures, but I am suspecting that when the bump is engaged, the 470k in series with the pot is paralleled with the 6k8, making it a kind of variable tonestack lift, with a minimum value of 6k7. yet another qu...

Awesome, thankyou for sharing! I do wonder about the bump level though: So, you have drawn the 470k resistor in series with the 500kA pot. I have tried this out in my version, instead of the 1M pot and the 10k I had there. But this arrangement makes the bump level have no effect on the sound... Also...

Im trying hard to trace out the bump volume circuit, but I must be seeing it wrong.
Following the wires, It seems to me to go like this: But this makes no sense - the 6k8 would never have a connection to ground like this....

Thanks. The schematic was what I could glean from other pictures and info I could find - coupled with a few personal edits. Some of those values were taken from other gutshots that some kind souls shared with me: The R10/R11 is a +/- switch on some of the models. The switch just parallels the 15 wit...

Sorry for waking up an old thread, but I thought it'd be better than creating a new copy of this... I'm planning a build of a DR, and is considering the whole grounding scheme. Right now, Im leaning towards Martin Mannings way of doing it. However, if I understand correctly, he has both channel's in...

how does this schematic stack up against it?

Hey. Im planning a DR build, but I might buy a blank chassis and have the front a bit different (mid pot, others..) Anyways, I wonder if anyone would have a precise drill template, or faceplate graphic with correct measurements that I could use to work from? I havent been able to find anything with ...

Hey. Im planning out a build of a blackface Deluxe Reverb. Now, I am looking over HoffmanAmps schematics, and see that he has implemented a different tremolo in his version. So now of course I'm curious. I think I have found various clips on youtube that to some extend showcase the difference in the...

thx

Ok, it's been quite a while, but this weekend I got back to messing with the amp. And I think I have solved the issue. I was a bit concerned that there was going too much voltage across the pi, so I though about ways to lower the voltage a bit. In the end, I remembered reading about putting some cur...