Incredible Dynaco st 70 stereo tube amplifier.  With the help of Bob Tucker, the ST-70 was designed in 1959 to reduce distortion and improve audio quality with four EL34 output tubes, a GZ34 rectifier tube, two 7199 input driver tubes, two ultralinear output transformers and a power transformer. At the time, solid-state amps were dominating the market and the ST-70 was available at a surprisingly affordable price. More than 350,000 ST-70 amplifiers had been sold when production finally ceased, making the ST 70 the most popular tube power amplifier ever made.

Works perfectly.  Beautiful addition to any serious collector.