DIY vintage amp rebuild/maintenance

[ENOCHKANE]

Hello everyone

I have been thinking about working on an amp I have for some time. I took it to two NYC amp techs and both gave me pretty much the same estimation of what is wrong with the amp (albeit with a HUGH different between the costs for the repairs). Anyway, i'm pretty handy with a soldering iron. I've done some amp repair work at the studio I work at and can trouble shoot, but i'm just worried about getting in over my head with this amp.

So, the amp is a 1963 Ampeg Super Echo Twin (ET2B model). I have a schematic for it and I do know that it needs to be recapped, has a couple of bad tubes (not super sure which ones, but definitley a couple of power tubes) and the reverb tank is shot. The amp works right now it's just very overdrivien at low volumes.

I dunno, maybe the recapping is OK to do and the reverb tank, but should I leave the tube issues to a real professional? Maybe I could buy the tubes and bring them to the tech (I know they charge more to make some money on them).

Sorry for the long post, I just wanted to see if anyone else has done something like this before. Maybe there's good book out there with tips....

Thanks!

Patrick

[mixedupsteve]

Changing tubes is the easiest part. What scares you about the tube change?

[ENOCHKANE]

yeah, I'm not scared of actually taking out and putting in tubes. It's the biasing of the amp after replacing the tubes. Also, I don't have a tube tester so i'm not sure which ones exactly are bad. This amp has two pre-amp tubes (6SL7) and two power amp tubes (7591), all of which are pricey so i don't wanna buy all four just to test it out.

any thoughts?

[paully]

Patrick, there really isn't any bias adjustment for that amp, and it shouldn't need it if you use a couple of matched 7591 output tubes. If you use non-OEM types other than the 7591, rebias may be necessary, but is not advised for DIY. With these old amps, the best starting point is a cap replacement at the power supply. They're the real culprits in most cases.

If you need some serious Ampeg help, go here http://ampegv4.com/index.php , grab a name and password, and repost in the Forum. All Ampeg all the time, and knowledgeable folks. It's more than just V4s.

Stay away from this site http://usedampegs.proboards.com/index.cgi . Infested with spam, and the moderator(if there still is one) doesn't seem to care.

Best, Paul

[Mach Schnell]

Hello everyone

I have been thinking about working on an amp I have for some time. I took it to two NYC amp techs and both gave me pretty much the same estimation of what is wrong with the amp (albeit with a HUGH different between the costs for the repairs). Anyway, i'm pretty handy with a soldering iron. I've done some amp repair work at the studio I work at and can trouble shoot, but i'm just worried about getting in over my head with this amp.

So, the amp is a 1963 Ampeg Super Echo Twin (ET2B model). I have a schematic for it and I do know that it needs to be recapped, has a couple of bad tubes (not super sure which ones, but definitley a couple of power tubes) and the reverb tank is shot. The amp works right now it's just very overdrivien at low volumes.

I dunno, maybe the recapping is OK to do and the reverb tank, but should I leave the tube issues to a real professional? Maybe I could buy the tubes and bring them to the tech (I know they charge more to make some money on them).

Sorry for the long post, I just wanted to see if anyone else has done something like this before. Maybe there's good book out there with tips....

Thanks!

Patrick

Take it to Dennis Kager at central jersey music. Those amps are getting rarer by the decade!