Elysia nvelope 500, Stereo pulse shapers, Discrete Class-A topology, Full range mode, Dual band mode, EQ mode, Mixed mode, Dual Mono / Stereo Link, Auto Gain, Scratched potentiometers, Frequency range: <10 Hz - 400 kHz (-3.0 dB), Noise A-Weighted Full Range: 20 Hz - 20 kHz -90 dBu, Noise A-Weighted Dual Band: 20 Hz - 20 kHz -87 dBu, Dynamic absorption: 20 Hz - 22 kHz 112 dB, Maximum level input / output: +21 dBu, Input impedance 10 kOhm, Output impedance 68 ohms, Scope of delivery: nvelope 500 module without frame, Construction: API Series 500 Format (2 Slots)