Very rare guitar amp from Japan maker Guyatone

This 1979 Guyatone EX1 amp is very rarely seen outside of Japan. It was most likely built and sold for the domestic market only. I found this one in a used music store in Portland, Oregon and suspect maybe a U.S. service man or woman brought this amp over from Japan.

The EX1 is an analog,  single channel, solid-state amp with 20 watts of power, a 12-inch speaker, overdrive and reverb. Gain and volume controls, high and low EQ, reverb depth. Normal and overdrive inputs, headphone jack, pilot light.

I had this one serviced by Audio Synapse in Portland, and had a new reverb tank installed, as the original was ineffective.

This amp is bright sounding to begin with, and the 12-inch speaker by Tokyo Sound Co. only makes it brighter. I replaced the original with a Peavey Neo and that added a lot of lower end.