The Parasound Halo A51 boasts cutting-edge amplifier technology, meeting the high standards of quality and performance set by Parasound. This results in an exceptional audio component with unmatched durability and long-lasting enjoyment. Key Features: Circuitry designed by legendary John Curl THX Ultra2 certified High bias Class A/AB operation Balanced inputs with discrete circuits and XLR connectors Direct Coupled - no capacitors or inductors in signal path Complementary MOSFET driver stage and JFET input stage 40 beta-matched 15 amp, 60 MHz bipolar output transistors 2.2 kVA encapsulated toroid power transformer with independent secondary windings for each channel 164,000 μF power supply filter capacitance DC Servo and relay protection circuits AC present, channel status, high temperature indicators Heavy-duty 24k gold-plated 5-way speaker terminals Gold-plated RCA input jacks; ground lift switch Auto turn-on by 12v trigger or audio signal 4u Chassis, carry handles, rack mounting adapter included