Masco "Audiosphere 100"

Anyone ever come across one of these?

It's a 6550 push-pull PA amp. It's a large and heavy amp, with a real, real large PS xformer. 5Y3/5R4 rectifiers with chokes, 6AU6 for input drivers with 12AT7 and 12AU7.
The OPT is pretty enormous for a PA amp.

Dunno if I'd ever find a mate.....this thing would seem like it would a make a rather nice bass or guitar head...

I'll try to post a pic later......

Can't find a schematic online. Oh well, I guess I'll trace it out.
Then there is always someone who has to hack into the amp.....always.....

Not listed in the Sams index, though there's an "Audiosphere 27"...

wow, giant rusty xformer on the loose

nice, like the knobs also

Wow, how cool is that?

Where did you come across that monster? Looks pretty nice. Have you listened to it?

I aquired the amp from a local audio friend who is moving and didn't want to pack and lug the thing. I think he's having a little remorse, however. It's worth more than I paid. It may be prudent to split the difference with him if and when I sell the beast.

A little bit of surface rust on the transformers, It'll come off. I doubt it harms anything.

Thanks for searching Tom, I appreciate that. Strange Sams doesn't have it.

I searched for a good 3 hours the other night for the Masco "Audiosphere 100", and I did recall something about the Audiosphere 27.
There is a older '50's era Masco PA amplifier of lower wattage, and is a popular unit for Blues harp players from what I read the other night.
There is a "Audiosphere 8", which is a little single-ended 6V6 or 6L6 PA amp.

It looks like the 100's little brother, with the same style cage and faceplate. With just two white knobs.

I think I seen the Audiosphere 100 schematic listed on a online site where you have to pay for it......maybe not....hate to have to pay for one.

I would be nice because somebody had added a choke underside, and set it up for fixed bias. It doesn't look factory to me, because the bias pot is parked way too close to the PS transformer. It kinda melted the little plastic knob they used.

The choke underside doesn't look factory by the screws, and the way it was mounted. It looks cobbled to me.

The tape on the PS wires is pretty good sign of non-factory work, and just they way things are layed out in that area.

The tube layout sticker on the chassis has a indication for a hum pot, but there is no indication for a bias pot. I would think that would be shown on the sticker.
And only one pot for bias. You'd think they would have used two pots. With test points for checking on the top side.
EDIT: What am I thinking....it's a mono amp...duh...

I'm guessing it was a self-biased amp, converted to fixed bias.

Haven't listened to it, I need to see it will even work first.