The Pioneer Spec-2 was a solid state amplifier not a tube amplifier. It was one of the best amplifiers of the 70's. 250 WPC @ 8ohms, almost 500 WPC @ 4 ohms. It was a monster! Now the bad part. The amp is going on 25 years old and the capacitors are sure to be dried up and not performing to anywhere near specs. If the amp is in really good shape, a complete rebuild may be in order. One of the best tech out there on old equipment is
EchoWars@kc.rr.com
He goes by EchoWars on audiokarma.org