Open Box version of the Unison Research Reference Pre. Limited quantity available. See the full Unison Research Reference Pre Listing for product details. Specifications Type: Valve preamplifier, dual mono, two chassis Tubes: 2 x 300B, 2 x ECC82, 4 x ECC83, 6 x 6C45P Phono Tubes: 4 x 6C45P, 2 x ECC83 Operation: Pure Class A Inputs: 4 x RCA, 2 x XLR, 1 x Tape, 2 x Phono Outputs: 1 x RCA, 1 x XLR, 1 x Tape (active), 1 x Subwoofer (active) Power Link: Power-on link for Reference power amps Input Impedance: 47k Ohm Phono Input Impedance: Selectable resistance and capacitance Gain (Preamp): 20 dB Gain (Phono): 45–55 dB RIAA Equalization: Passive ±0.2 dB Bandwidth: 10 Hz –> 100 kHz @ –0.3 dB Negative Feedback: 15 dB line, 0 dB phono Distortion: 0.1% Power Consumption: 320 W max Dimensions: 45 cm x 56 cm x H 22 cm Net Weight: 30 kg / 66 lbs