A really good early 1970's amplifier. All these early Pioneer models sound really good, basic facilities in the best meaning of the word, later on lots of meters, flashing lights and far too many controls reduced the sound quality of a lot of Japanese amplifiers, Pioneer kept it clean for a long time. The speakers were designed to connect with special plugs that are very hard to get these days but it's not too difficult to come up with an alternative jury rig that will save changing out the speaker sockets; they were just flat blades mounted in an oblong plastic block with screws to attach the wires. You won't regret buying a good one of these, or its baby sibling, the more common SA500.