The Amp Garage

solderhead wrote: ↑Fri Apr 11, 2025 11:35 am

WiderGates wrote: ↑Fri Apr 11, 2025 9:07 am The Twin is not the Evil Twin!

Uh-oh. Am I looking at the right schematic? I was looking at this one:
TheTwin.pdf

That would be the one!

solderhead wrote: ↑Fri Apr 11, 2025 8:06 am I could post the math here for how to calculate all of the frequency poles for the NFB loop but I swear that nobody is going to want to read it.

Please do!

xtian wrote: ↑Thu Apr 10, 2025 3:50 pm Evil Twin has FX loop? Divide and conquer.

Thanks Xtian, hadn’t considered that. I bypassed the FX loop with no change

Even if the caps look fine, they might still be dried out or failing. Same goes for resistors, especially plate or screen resistors. Swap out your tubes if you haven’t already, especially the power and phase inverter ones Changed out power and preamp tubes. No change. Tried pulling preamp tubes one...

I have a Fender The Twin red knob that’s giving me issues. The guy I got it from says it was worked on by a tech and it came back to him like it is. After warmup it has a hum in both channels with volume all the way down. When playing, the output is dirty with a weird octave ghost note on single not...

I should mention that hot hide glue may be modified to have considerably longer open time, like the addition of urea or (believe it or not) table salt. I've used the table salt method for years, but reverted to straight hide glue for my guitars. Heating the parts before assembly is critical to get ...

I was initially impressed with the results. With time though all of my joints have opened up after only a couple years. Now it's getting harder to find the solvent based stuff, but that's what I'd go for on anything from here out. I’ve done a couple of cabinets with water and solvent based contact ...

I have a cab I need to Tolex and am thinking about using hide glue. Is there anything special I should know about it or things to be aware of with using it?

Stevem wrote: ↑Fri Jan 12, 2024 11:10 am Vishay makes good ones, Panasonic makes some of the best, but they can be hard to find in the needed tube amp voltage ratings.

xtian wrote: ↑Fri Jan 12, 2024 4:45 pm Panasonic and Nichicon are the ones I used most often, purchased from mouser.com.

That helps. Other than voltage ratings, what should I look for, for a filter cap?

Does anyone have a recommendation for a good brand of Radial lead caps for filter caps?

I came across a Fender Deville for a good price but the faceplate is rusted. Where would I get a good replacement faceplate for it?

Ok it’s all good now. After the new resistors and reflowing solder on the phase inverter socket and ribbon cable, fire it up and it works great!

Thanks for the help everyone!

Are you plugged into the correct speaker jack ? It happens, not being snarky,.. if your in the second jack, you’ll get shit for output.. No offense taken. I used to do computer maintenance. I don’t know how many service calls I went on only to find it wasn’t plugged in! Its the simple things... Had...

bad PI tube bad plate load resistors. They fail all the time (crap part). Replace both with one watt. Usually one dies, rare for both, but it's a start. :) Thanks fuchsaudio. Replaced both of them and at least have sound now. Output is very low though and it distorts around 3 or so on the clean lik...

I have a Fender Hot Rod Deville that was given to me by a buddy. I don’t think it’s more than a few years old. It had stopped working and he didn’t want to fix it. He said it had sound when you turned it on but it would get faint and just stop after a couple of minutes. I couldn’t get it to make any...