This is one of Krell's first KAV 500 5-channel amplifiers. It may be used in 2,3,4 or 5 channel modes. You could bi-amplify your speakers or use it effectively connected to a passive subwoofer. It has been just serviced by the best technician in western Florida and a receipt will be provided. It is in great working condition and the faceplate has been newly powder coated. Built like a Sherman tan, it will drive any speakers of low impedance. It weighs 47#. You may use either single-ended RCA cables or balanced inputs. Designed in are gold plated 3-way speaker binding posts. It produces 100 watts/channel into 8 ohms, 200 wpc into 4 ohms continuous, all channels driven; or 400 Watts/Channel bridged (2 channels) THD < 0.03% Input Impedance 100 kOhms Original Price: $4,500 5 Channels The last image provides the impressive design architecture including the robust torroidal transformer and the massive filter caps.