Rare (truncated) pyramid shaped stereo power amplifier from Yamaha. At the heart of the Yamaha B-6 from 1980 is the so called "X-Amp" scheme. Initially known as "X-Power", this power scheme was first used in the Benytone X-Calibre lineup and the Carver lineup they were building at this time. It seems that Yamaha, as a later adopter, for some reason didn't implemented fully the Benytone/Carver technology so it was renamed "X-Amp". Basically this system is using a TRIAC which switches between high or low power supplies according to the input signal and output needs. This results in increased output power capacity, but some say that it is not necessarily a good sound too. (200 W/ch 8Ohm, THD: 0,003%, 10-100.000 Hz, 29 x 17,65 x 29 cm, 9,2 kg)