“Super easy to get a good sound out of
the TNB-1 depending on the sound quality of your rig. Four pots — bass, treble, gain, and output level.”
in Japan perhaps in the mid-1980s. Low noise but with
tons of gain and tone sculpting ability courtesy of the separate volume,
gain, bass and treble controls. Side mount in/out
and takes a standard 9v power adapter.”
More information here.