It is common knowledge that Rickenbacker invented the electric guitar. Doing so, they had to invent the guitar amplifier as well.
Rickenbacher started making amps as long ago as 1930. After a couple of early production models they came out with the M line of amplifiers the first written evidence of which is a1933 catalog referencing an M-10, an M-11 and an M12. These amps predate the homonymous M-XX series built in the fifties.
Hal Lindes of Dire Straits fame, an owner of an M-11: "I have heard Leo Fender used to repair Ric. amps at his TV repair shop, which probably inspired and gave him the blueprint for his Fender amps."
This is a 1930s Rickenbacher M-10 Guitar Amplifier and a companion to the Rickenbacher A-22 frying pan lap steel guitar (see TYS electric guitar collection). It has a single Utah 10” speaker. The M-10 amplifier has two 6V6, one 5V4 and one metal 6N7 tubes. There are two jacks and power switch on the back. No volume/tone controls.
This amp was built in various versions and it is difficult to assess correct period of production. Based on the layout it has to be built between 1936 and 1940.