1950s Stromberg-Carlson AU-33 35w Modded Tube Amp Head

This started-out life as a PA system amp (hence why it's got three microphone preamp channels) but Mr. Winfield Holt of Orator Amplification did some heavy-lifting modification of this amp to make it a 3-channel guitar amp. It's rated somewhere between 30-40w, breaks-up nice and early, and gets pretty loud when you want it to.

It has all sorts of strange features. First-off, there's only one input jack and then there are flip switches to turn on or off whatever mix of channels you want to add into the total output. This gives all sorts of tone-shaping right-off and each channel has its own sort-of EQ curve and response. Overall, I think the whole amp gives you an almost "horn-like" attack -- when driven you can get lots of sustain that feels almost compressed (in a good way) and "barky" like a trumpet. It's a fun chord-chomping amp but it's coolest for lead sounds. Think Charlie Christian vibes!

Other features, though? There are bass and treble controls which I left, essentially, up during the demo. There is a middle-panel switch that says "phonograph" but instead works like a rudimentary attenuator with three positions (full power, supposedly half, supposedly quarter) and your mileage may vary with it in terms of audible power and its perception. I liked it in the middle (quarter power) which is where I left the amp during the demo as I recall. I don't think the overall tone changes all that much when the power level is dropped-down save that I didn't need to trim off as much bass at the lower settings.

There's switchable speaker ohm ratings which is nice when matching it with different cabs, too.

Lastly, Winfield added a handle to the case and replaced all the missing knobs with modern reproduction-style ones that fit nicely on it. It's ready to serve!