The amplifier comes from the family of multi purpose amps that have 3 differently voiced inputs and can be used for either guitar, bass or organ (hence the name GBO). It's an open-back combo type amp that features one 12'' Marlboro special designed M12Q speaker and is labeled at 37 watts of power. Just like its ''older brother'' GBO-15B, it has only three controls on the frontplate: volume, bass and treble.
I would like to thank Arthur D. for sending me the pics of the amplifier!
