This is a Radio Station Mixing Console made around 1945 - 47. It mixes three microphones, two pronograph turntables, (when a music record was played) and one line level signal. 

The mix is sent to, either out on the air, or back to the studio, or listening audience

I managed to get all of it running fine again, NO CIRCUIT INFO, and it sounded warm and smooth.

It had dual power supplies, a lot of 6sc7 tubes and a internal monitor amp and speaker.

Another Summer 2020 amp Mod job for one of the Carlsbad, CA 'Moose Lodge Players' amps was this Marshall 18 Watt amp. I made it cathode bias for more compression and smooth Blues Tone, all carbon resistors, and changed over to 7199's for a real 24 watts out.
 

 A recent modding job for a great Oceanside, CA player, is a Tweed Twin amp with four EL34 tubes in cathode bias for much less power and much more compression. Also using carbon resistors in the audio paths, the plate and cathode resistors etc. for big tone and smooth compression. A 12at7 driver and vintage 12ax7 tubes for the preamp. This was done at the http://tubeamprepairshop.com/ really messy bench, from the huge amount of amps that have been here before. Summer 2020