More on Amazon.com : http://www.amazon.com/gp/product/B0008GG910?tag=purrfectcatdi-20

QSC ISA500Ti 2 Power Amplifier 2 Channel Rack Mount Stereo 500 Watts per CH 70 Volts ISA Series

25- 70- 100 volt and low impedance outputs available simultaneously
Simple barrier strip connection determines output mode
Rear panel gain controls for tamper resistance
XLR and detachable Euro style input connectors