So I bought a thing today...

[bobyoung53]

I like how it says 35 watts right there on the can. Especially since Ampeg was famous for underpromising and overdelivering.

It's a good sounding amp, almost hifi, it's got some power too.

 

[Jeff Michael]

An update...

I am approaching the conclusion that I blew it, in a nutshell.

The initial purchase of the amp I can still stand behind. It was expensive, but it was a unique, historical object in close to pristine original condition.

That's where I should have left it. At this point I feel like I caught a unicorn, and then sawed off its horn to use it as a horse...and it never worked as a horse afterward anyway.

The first phase of "getting it into workable order" was a vintage radio restorer. I figured as it was from the 1940s, it was probably more within that bailiwick than a typical amp repair guy. I can still stand behind that logic. Even though I think dicking around with it was in retrospect a mistake, that first decision was sound.

The radio restorer, though--that was a whiff. I ended up with a bag of vintage components, an amp that doesn't work, and about $500 less than I had before I started. I should have known I was in trouble when I asked the guy to take pictures of the guts before he started replacing anything and he didn't get why I would want that. He thought I thought he might be scamming me, I think. And here, by the way, are the pictures he provided:

I definitely blame myself somewhat for not making my wishes clearer. And I can't even say that the vintage radio guy wasn't good. I don't know what the radio restoration game's expectations are. Maybe vintage radio owners are perfectly happy with their vintage radios cleaned up and working properly and don't care a whit about what's under the hood or historicity or whatever.

Of course, the whole "working properly" thing is where that all breaks down, because it didn't. Now you'd think that maybe I should have said 'hey, you fixing this didn't work' and demanded he get it going. But again, I was feeling very protective of the amp, and if this guy didn't nail it the first time, I didn't want him back in there doing more of what didn't work in the first place. It's like if you get your hair butchered, do you go back to that barber to fix it? I wouldn't.

So I took it to a regular "amp guy" that I know who's very very good. He's worked on my B15 before and knows the amp game, versus, you know, being a vintage radio restorer.

And he's flummoxed. There's no schematic, of course, and there seem to be gremlins that he just can't pin down. And he took the questions to his mentor, who is pretty much THE guy around these parts, and it's still a mystery.

It's been months and months, and hundreds and hundreds of dollars, and now the time machine relic I paid dearly for is a baggie of original components and (maybe eventually will be) a mostly-new amp in an old wooden box...that is, by virtue of being 18 watts, is essentially useless in the field anyway.

Again, I don't know that the decisions I've made with this amp were ill-advised or unwise, nor am I particularly disparaging the craftsmen I've brought in on the project. But having come this far, nah...I should have left it be.

 

[Brian Patterson]

Museum piece - does it work?

 

[2saddleslab]

An update...

I am approaching the conclusion that I blew it, in a nutshell.

The initial purchase of the amp I can still stand behind. It was expensive, but it was a unique, historical object in close to pristine original condition.

That's where I should have left it. At this point I feel like I caught a unicorn, and then sawed off its horn to use it as a horse...and it never worked as a horse afterward anyway.

The first phase of "getting it into workable order" was a vintage radio restorer. I figured as it was from the 1940s, it was probably more within that bailiwick than a typical amp repair guy. I can still stand behind that logic. Even though I think dicking around with it was in retrospect a mistake, that first decision was sound.

The radio restorer, though--that was a whiff. I ended up with a bag of vintage components, an amp that doesn't work, and about $500 less than I had before I started. I should have known I was in trouble when I asked the guy to take pictures of the guts before he started replacing anything and he didn't get why I would want that. He thought I thought he might be scamming me, I think. And here, by the way, are the pictures he provided:

View attachment 7032382

View attachment 7032383

I definitely blame myself somewhat for not making my wishes clearer. And I can't even say that the vintage radio guy wasn't good. I don't know what the radio restoration game's expectations are. Maybe vintage radio owners are perfectly happy with their vintage radios cleaned up and working properly and don't care a whit about what's under the hood or historicity or whatever.

Of course, the whole "working properly" thing is where that all breaks down, because it didn't. Now you'd think that maybe I should have said 'hey, you fixing this didn't work' and demanded he get it going. But again, I was feeling very protective of the amp, and if this guy didn't nail it the first time, I didn't want him back in there doing more of what didn't work in the first place. It's like if you get your hair butchered, do you go back to that barber to fix it? I wouldn't.

So I took it to a regular "amp guy" that I know who's very very good. He's worked on my B15 before and knows the amp game, versus, you know, being a vintage radio restorer.

And he's flummoxed. There's no schematic, of course, and there seem to be gremlins that he just can't pin down. And he took the questions to his mentor, who is pretty much THE guy around these parts, and it's still a mystery.

It's been months and months, and hundreds and hundreds of dollars, and now the time machine relic I paid dearly for is a baggie of original components and (maybe eventually will be) a mostly-new amp in an old wooden box...that is, by virtue of being 18 watts, is essentially useless in the field anyway.

Again, I don't know that the decisions I've made with this amp were ill-advised or unwise, nor am I particularly disparaging the craftsmen I've brought in on the project. But having come this far, nah...I should have left it be.

Live & learn. Worth the effort IMHO.

About 30 years ago a friend gave me a 1958 Philco Predicta, in non-working condition. Took it home and completely disassembled it just to see how it was made. Put it back together and left it until I played a gig in Aurora, Indiana and while on break I was a the bar talking about it w/ my drummer. The bartender overheard the conversation and showed me his Philco TV Repairman card. He wrote down the components I needed and schematic on a bar napkin. I gave it to a kid who worked on TV and damned if he didn't get it working. Also, I had to send the TV tube to Texas to get re-vacumed.

We watched Schindler's List on it and did a photo shoot w/ Elvis on Ed Sullivan via a VCR. Alas, I heard a bang, saw some smoke, and turned it off. probably a bad transformer. I know a guy in Seattle who said he could fix it but not sure I'm up for it.

 

[agedhorse]

This is unfortunate yet common in the “restoration” world, list of big talk but mostly under-delivered results.

This is exactly why truly qualified, experienced techs first analyze and diagnose rather than jump in and replace (many) perfectly good parts. I mention this often here because the world is full of really crappy techs posing as qualified.

 

[Patrice B]

As you said, schematic nowhere to be found. Maybe ask Yamaha if they have it in their old files somewhere?

Bummer

Better clear pics of the underside before? Someone could probably decipher a schematic just looking at it.

 

[Patrice B]

1947 Ampeg Michael-Hull Bassamp Bass Guitar Amplifier. The worlds rarest amp!

The 1947 Ampeg model 770 with MOTS covering was though not to exist. The only known photo of one was in a Michael-Hull flyer from 1947...until today. Introduced in 1946, the Ampeg Bassamp was the first commercially available bass amp sold. The original had a mahogany cabinet. Michael-Hull...

www.mylespaul.com

https://www.talkbass.com/threads/1946-ampeg-michael-hull-bassamp.1175392/page-2

https://www.abalonevintage.com/1947_ampeg_770_bassamp_bass_guitar_amplifier_MOTS_combo_rare_amp.htm

EDIT: maybe you could ask member @greenbass5 for better pics of an unmolested unit?

 

[Jeff Michael]

1947 Ampeg Michael-Hull Bassamp Bass Guitar Amplifier. The worlds rarest amp!

The 1947 Ampeg model 770 with MOTS covering was though not to exist. The only known photo of one was in a Michael-Hull flyer from 1947...until today. Introduced in 1946, the Ampeg Bassamp was the first commercially available bass amp sold. The original had a mahogany cabinet. Michael-Hull...

www.mylespaul.com

https://www.talkbass.com/threads/1946-ampeg-michael-hull-bassamp.1175392/page-2

https://www.abalonevintage.com/1947_ampeg_770_bassamp_bass_guitar_amplifier_MOTS_combo_rare_amp.htm

EDIT: maybe you could ask member @greenbass5 for better pics of an unmolested unit?

I thank you for bringing this to my attention! However, a quick peek at the @greenbass5 pics makes me think that wouldn't be as useful as one might think. The amp configuration looks more like my 1951ish Super 800 model Ampeg Bassman, if only because the amp chassis sits on the bottom of the cabinet instead of being mounted on the side.

The more I see of these pre-Ampeg Bassamps, the more I am inclined to think that literally none of them are alike.

 

[B-string]

Well that is depressing to say the least. The first step the "radio guy" should have done is attempted to create a schematic from the chassis. Many of these era electronics were unmolested or minimally molested circuits from the back of an RCA or GE Receiving Tube Manual. The problem there, which release version of those manuals. If your amp was designed around the metal 6L6 output tubes and you now have glass 6L6G,GB or GC this is a mistake no "restorer" should make. They do not interchange directly. Same applies to metal can 6SL7, 6SJ7, 6SN7, 6J5 and so on. If you have glass bottle sub'ing metal can that may be your biggest concern.
I hope this can be brought back from the brink. A few caps, a resistor and a metal 6L6 if that earlier photo applies to your amp gives "hope" he did not do any serious damage.