Tube Amp Archive

@beasleybodyshop, in the video you posted about measuring the impedance of the OT he used a variac (sp). Don't have one of those so is there a way I could simulate what he is doing by some other method? There are some percussion transformers on the ao-29 that I am looking to possibly use for the rev...

Okay, so after just using my brain and deciding to look at the schematic, I see that there are three transformers used for the percussion amplifier. I'm trying to find some information about them to see if possibly I could use one for my reverb transformer. Someone mentioned this possibility here ht...

Okay awesome, that will be the plan. Did you mess around with any of the other transformers inside of the chassis? At least that's what they look like from the outside. Looks like a couple smaller transformers maybe? Just wondering if that's what they are, would they be good for anything.

It was powering a pair of 6V6GT's so I'm thinking maybe it doesn't have quite the juice for the 6L6?

From what I've seen there are some ao-29 that have the pm and some have field coil. I don't know if the -13 specifies the type. My it is A024924 0
524 65 17.

This weekend I'll check and see what my actual voltage coming out of the PT is. Hopefully nothing extra will be needed. I'm planning to use the 5U4GB that came with the amp as my recto. Any experience with the field coil OT? It says to use with an 8 ohm speaker but also has two 100 ohm resistors on ...

Yeah, that makes sense just going off of the schematic to get everything I need. Just don't want to miss anything, but that's on me. If I went with the TR I'm not sure if I would be able to use the PT and OT out of the hammond organ I bought. That will probably be the deciding factor, because I don'...

Hmm, that definitely makes me reconsider. The PR and the TR are my two favorite amps, but it would be really fun to have a TR. I guess what makes me more nervous about it is coming up with my own BOM. I've bought a hammond ao-29 and I plan to use the PT, OT, chassis and tubes for whatever I build, s...

Thanks, that is definitely helpful. I'm looking forward to seeing how your build goes. I'm probably going to end up doing a PR this first time but next I would really like to the the JM TR.

Alright so I've been reading and reading and reading a lot of the threads about doing a hammond conversion, and I am at the very beginning of my own. I bought an AO-29 with all working tubes on eBay for $60 total. Here are a few pics. My plan is to gut it out and use the chassis, PT, OT and tubes to...

Okay, so I'm considering building a JM series Two rock 50W head. I did find the d_jm_967 schematics that have been posted. Does anyone have a good BOM to go off of? I've been considering doing a PR but really like the tone from a two rock. Any suggestions and resources would be greatly appreciative....