Tube Amp Archive

You can't use the Super OT because the turns ratio is wrong (unless you change your speakers). You could use the Bassman OT. It might give you more bottom. But unless you're sure the problem is with your OT, it won't necessarily fix it. my problem is that I have a great sounding amp[- and i just wn...

am I wrong in thinking that I would get a nice increase in headroom and bass power by replacing my pro reverb's OT with the bigger OT's that are found in either a super reverb or a bassman? I've seen the super and bassman- and they are bigger in size... am i wrong in thinking this means more headroo...

So I was thinking of putting larger transformers in the amp like Super Reverb Sized. My questions are- Should I replace both power and output... I know replacing the power transformer I would have lower voltages and be able to use a GZ34 or SS rectifier to get that punchy twin sound. I don't know w...

I have a Pro reverb- and while I've loved it for many years my current situation is deeming it to not have enough headroom. When I first got the amp it just had a ridiculous amount of headroom- but it was colder and more sterile sounding- right now it sounds pretty dang good. It breaks up around 5-6...

FIXED! Now I'm back to the original things I dont like abotu the amp! Should I upgrade transformers to super reverb sized? Should I just do output? Or should I do both output and power so I can use a GZ34 rectifier without overly high voltages? Thanks for the help everyone! It turned out to be one o...

Ok you've proven that the distortion you are hearing is not an oscillation on the power supply. I'd put it back to the original wiring and fix up the lead dress. That might help with the distortion and with the brightness. Mixing lead-free and tin-lead solder is generally frowned upon, with possibl...

Caveing, if you want to give this a shot here's an easy mod to test the theory of what Colossal is saying. This splits the power supply for the reverb recover and mixing stage from the preamp gain stages without getting into the doghouse. The electrolytic I show as 22uF, it could be 16, or even 10....

Looking at the gut shots I'd say that you could tidy up the leads a bit. Look closely at the Fender layout drawing and try to make your leads from the board to the tube sockets look more like that. The leads going to the power tube grids seem out of place... I think I'd reroute those and in general...

For starters, the 180k plate load is going to distort the signal very soon. Also, Did you check/replace the PI tube? A weak one will cause major distortion. that entire mod really didnt change the gain that much- more affected the eq. but that's the normal channel- the vibrato is completely stock a...

here are some pics of the amp
sorry, dont have a good camera or a very steady hand (it requires more steadiness than anything i have ever attempted- samsung and sprint suck!!!!)

I'll hopefully have a chance to try the stuff above tonight.

...and "martinmanning"- did you mean to post a link or a graphic with your post? It's there, you have to be signed in to see it. Maybe you should post some good pics of the insides of your amp? Got it! thanks. Can i try that with a 22uf 350v? I have one of those on hand. or does it have to be 450v?...

The voltage on the plate of the 1st half of the trem tube should be "high" when the trem is in its default mode (off.) This is because, with no pedal switching it on, the negative bias circuit has its 1st triode turned off. The 2nd triode should be "high" as shown in the schematic. Sounds like you ...

Though my high notes do have a weird reproduction on them... kinda sitar like... not too bad, wouldnt notice it too much in a full band situation, but if you're listening carefulyl its pretty annoying. This sounds like "ghost noting". If you look at the AA763 Vibrolux schematic (and most Fenders), ...

sometimes parasitic oscillations can sound like distortion - check lead dress, especially if its a silver face Fender and you were moving stuff around or removing ceramic caps etc sorry if I came off like a dick there. Could the parasitic oscillation sound like halfway decent overdrive? I mean it r...

sometimes parasitic oscillations can sound like distortion - check lead dress, especially if its a silver face Fender and you were moving stuff around or removing ceramic caps etc ill try to move wires around- i've done tons of this, but have only found mild changes in noise levels and whatnot. but...