Wow! That is an old one. The "smiley face" logo plate was used on the Sunn amps when I was operating out of my dad's shop in Lake Oswego, Oregon before moving into the Tualatin location. The paisley looking vinyl was actually used on the old Pullman railroad car seats. This unit has a handwired Dynaco Mark III amplifier driven by a bass preamp of our design.
Conrad Sundholm
Co-founder of Sunn Musical Equipment Co.