Since you are looking to have fun, I suggest you look for an old Harman Kardon 430 or 730 receiver and use the amp portion only by removing the pre out to amp in plug and using the power amps only. These amps are dual mono with separate power supplies. The reviews of these receivers by High Fidelity Magazine showed that these amplifier sections were exemplary and displayed almost perfect square waves on both the high and low frequencies. You will be surprised at how good these amplifiers are. They can compare with very expensive equipment in performance. If you find these in a thrift store or in the flea market, if the fuse is intact, the unit is probably playable. Note also that the amps are individually fused internally. You should be able to find a good conditoned example for $20-$30. This is surprisingly fun. Keep us informed if you go this route. An alternate to this is to look for a built like a tank Harman Kardon Citation XII amp. Even Nelson Pass spoke highly of this amp in one of his early articles. He spoke of its durability due to build quality as well as the sonic performance of this HK-12.