The Amp Garage

Well quickly looking at the plate characteristics, the 5Y3 has a plate resistance of around 500 ohms, and the EZ81 about 150 ohms.

This means that the 5Y3 will sag and compress more with changing currents, and the EZ81 less.

(Noticed the Schematic Heaven post.)

I've built three Trainwreck Express type amps on my testboard with 12AU7 output. The truth is that there is no way to get power amp distortion even from 12AU7 within any reasonable apartment sound levels. No way. But otherwise it rocks very nicely. I shot a clip way back (with out of tune guitar, wh...

I recently built a Matchless Clubman preamp (driving a 12AU7 power section) with a 6SH7 pentode as per schematic. I read on Harmony Central reviews that Matchless has used EF86 in their later Clubmans, with some differences in tone. I have a good source for the 6SH7, and I've heard that the current ...

A while back I built a HiWatt DR103 clone, with a 12AU7 power section (NOS Miniwatt). I was very happy with the sound, it really does the Pink Floyd thing good. Lot's of balls as everyone said. Of course the sound isn't going to be as big as with EL34's, but to tell the truth I really don't have the...

I've come to understand that the Liverpool is somewhat in the range of Voxy sounds. I've built an Express, which to me is clearly in the ballpark of Marshall sounds. How much of a Vox would you say the Liverpool is? If you forget about the extra gain, how would you compare say AC30 and the Liverpool?

Nice touch with the knob rainbow!

I've heard that using bigger filter caps on your classic amp will effect the sound. How exactly?

What are the exact changes that take place tonewise when you for example change some 22µF filter caps to 47µF?

What is the theory behind this change, what does it do to the amp?

jjman, forgot all about Dolby! =D

John C, makes sense.


Apparently the Fender Bassman 6G6's have an almost identical solution, so I'm guessing Selmer borrowed that topology.

Structo, I absolutely agree that harmonics are very important for a bass guitar amp, but what's the point of 'boosting' the treble (or rather attenuating less but anyway) for those two stages after it, and then filtering it down again? The harmonic content that is emphasised with the tonestack is be...

I've been looking at a tube bass amp, the Selmer Bassmaster 50. Everything else is pretty much straightforward about it, but I'm a bit puzzled as to the voicing of the preamp. The (half passive) tonestack has a significant signal drop on the bass frequencies, a mid notch and relatively very high tre...

Which caps do you usually use on your 'Wrecks? I've seen a lot of folks use Orange Drops, some Mallory 150's.

Are cap brands critical in the Express? More than in some other amps?

Anyone tried Vitamin T's or other oil filled caps?

I have been modifying an Epiphone Valve Junior now for some time, finally deciding to try out a TW Express preamp. From sound clips and reading this forum I was under the impression that the Express would carry an excessive amount of gain and plenty of harmonic content - to my surprise my own little...

I was lurking around in Facebook the other day, and it seems there are communities to just about everything trainwreck, except Trainwreck amps. So I decided I'd put one up, figuring if Fender and Marshall are represented, why not Trainwreck. http://www.facebook.com/home.php?ref=home#/group.php?sid=2...