A 1950's advertisment for the Oahu Tonemaster. Like most of the Oahu
amps it was also sold as Supro and National.
1947 single ended lap steel amp.
1948 guitar amp; same circuit as the Tonemaster.
A 1952 Oahu Guitar amp.
Backside view of the same 1952 Oahu amp. The tube complement is
a 6SN7 input, dual 6V6 output and 5Y3 rectifier.
The 1954 version sporting the new and more familiar logo.
Backside view of the 1954 version. This was the ast year that they
used octal pre-amp tubes. For a short time period, all Oahu amps came with miniature input (either 12AY or
AX7) and a 6SN7 phase splitter. Starting in 1956 and thereafter, they used miniature input tubes only.
