the t.amp D4-500, Digital Amplifier, Class D, 4 x 500 W @ 4 O, 4 x 250 W @ 8 O, Frequency range: 20 Hz to 20 kHz, Connections: XLR inputs, speaker twist out, Temperature controlled, Low rack installation depth (only 240 mm), Design: 19""/ 1 U, Weight: 4.6 kg