Baldwin C1 Supersound Amp Schematics

[wagz]

I just got an old Baldwin C1 Supersound amp and I was wondering if anybody has schematics for this amp. Everything works on my Baldwin amp, but it begins to distort with the volume at about "4". It doesn't get much louder beyond that point. Instead, it gets very fuzzy. The problem is not the speakers. The sound is distorted even when using another cabinet. It sounds cool and everything(reverb, trem., Supersound, etc.) works, but I understand these amps are supposed to be loud and clean.
Please, if you still have schematics, let me know. I am not a tech, but I can give it to the local amp repair-guy in my area.

Also, if you know what the cause could be let me know.

[J M Fahey]

I just got an old Baldwin C1 Supersound amp and I was wondering if anybody has schematics for this amp. Everything works on my Baldwin amp, but it begins to distort with the volume at about "4". It doesn't get much louder beyond that point. Instead, it gets very fuzzy.

*All* amps distort beyond a certain volume.
Usually around 6 or 7 , but you probably have hotter pickups than those available in 1967, so distorting above above 4 does not mean it's "broken".
That said, clean it is, within its ratings, but 45W was "loud" ... in 1967, not much today.
This amp has a peculiarity: given the transistors available in 1967, it provides 45W RMS ... into 2 ohms.
The original speaker complement was 2 excellent Jensens (C12N?) but 4 ohms each, so they supply 2 ohms total.
If you plug this amp into a standard 8 ohms speaker, it will provide around 15 clean watts.
Even if it has the original speakers, of which I am not so certain after that many years, maybe they have been (improperly) reconed with 8 ohms coils.
Please check that.
Depends on what you play, but around 50W with 2 good and matched speakers (as it was originally made) provides good clean sound in a Jazz, Pop, Country or light Rock setting; not much of a sweet warm Blues machine and forget it for Metal.

The problem is not the speakers. The sound is distorted even when using another cabinet. It sounds cool and everything(reverb, trem., Supersound, etc.) works, but I understand these amps are supposed to be loud and clean.
Please, if you still have schematics, let me know. I am not a tech, but I can give it to the local amp repair-guy in my area.

The speakers may be working properly but not what this amp wants, please check that.
And don't fix what's not broken.
Here's the schematic (thanks Teemuk)

EDIT: right click and "open in new window" to see it full size.

[wagz]

*All* amps distort beyond a certain volume.
Usually around 6 or 7 , but you probably have hotter pickups than those available in 1967, so distorting above above 4 does not mean it's "broken".
That said, clean it is, within its ratings, but 45W was "loud" ... in 1967, not much today.
This amp has a peculiarity: given the transistors available in 1967, it provides 45W RMS ... into 2 ohms.
The original speaker complement was 2 excellent Jensens (C12N?) but 4 ohms each, so they supply 2 ohms total.
If you plug this amp into a standard 8 ohms speaker, it will provide around 15 clean watts.
Even if it has the original speakers, of which I am not so certain after that many years, maybe they have been (improperly) reconed with 8 ohms coils.
Please check that.
Depends on what you play, but around 50W with 2 good and matched speakers (as it was originally made) provides good clean sound in a Jazz, Pop, Country or light Rock setting; not much of a sweet warm Blues machine and forget it for Metal.

J M Fahey, thank you!!!! I really appreciate this. I'll check the speakers tomorrow when I go back to the shop. They are both stamped "4 ohms", but I didn't notice anything indicating that they were Jensen speakers. They probably are Jensens.
Anyway, I work at a shop full of vintage and modern guitars and the sound of the amp seems a bit clipped up to about "4", with even a standard USA telecaster. If you really lay into a note or hit a six-note chord hard, it will crunch. At "5" and up, and depending on the output of the pickups in the guitar, it goes from a Bluesy, Rolling Stone-ish fuzz overdrive to an all out super-compressed(or splattery) fuzz sound. This happens with all channels and inputs. It gets pretty nasty. Very raunchy.

Based on everything I've read about these amps and the word of one of my shop's regular customers who owned one of these amps when he was younger(He flipped when he saw this amp in the shop), it's supposed to be very clean sounding. I didn't get a chance to plug it in before he left. It would have been nice to have him verify that this amp operates the way he remembers them working. Anyway, it sounds pretty cool, but I'd like to get it to sound however it's supposed to.

EDIT: I forgot to say that this is my personal amp. I plan to use it for recording and live stuff. It's sounds cool and it's dead quiet.

[wagz]

*UPDATE*- The tech that I mentioned has had Baldwin C1 for for a few weeks, now. Anyways, he replaced the output transistors with some really expensive germanium transistors (like 30 bucks each) he had laying around. 
I asked for silicon (because they are supposed to be much less expensive), but he used germanium transistors. He says that he couldn't use silicon transistors because he'd have to re-design the amp. I think he mentioned that there would be some sort of bias issue.

He still has the amp, though. He says that it sounds really good when it's turned up loud now, but it chokes off the sound when the volume is low. I assume that he means it sounds gated.

J M Fahey, do you have any technical advice in regard to using silicon instead of germanium? Also, is it normal for this type of amp to choke the sound at low volumes?

[J M Fahey]

The amp is not only biased for germanium but the driver transformer expects germanium too, so it's wise to stick to it.

As of the "choking", you must hook  a scope at different points along the path and check what happens and where, while you hear that.
Can't guess, only "seeing" it will do.
Good luck.

[wagz]

Ok. I'm sure the tech will hook a scope up to it and figure out the problem. Thanks again, Mr. Fahey.