Audio Research Ref 10 Phono Stereo Preamplifier MSRP: $35,000 Color: Silver This preamplifier is in excellent condition and functions flawlessly. This is one of the best stereo preamplifiers you can get from audio research and it sounds incredible. It comes with the original remote, user manual, chassis interconnects, 20a power cord, and a zero hour tube set. Do not miss the chance to own this amazing preamplifier at an unbeatable price. Electronic SpecificationsElectronic SpecificationsFREQUENCY RESPONSE ± .2dB of RIAA, 10Hz to 60kHz; 3dB points below 0.3Hz and above 300kHz.DISTORTION Less than .002% at 1.0V RMS 1kHz output.GAINSelectable 51dB (Low), 74dB (High) at1kHz BAL; 45dB (Low), 68dB (High) at1kHz SE. (MC & MM compatible).BUTTONS Front (2) Power, Mute.INPUT IMPEDANCE 47K ohms and 100pF SE. Selectable loads 1000, 500, 200, 100, 50 ohms and Custom.PHONO EQUALIZATION(Selectable) RIAA, Columbia, Decca.OUTPUT POLARITY Non inverting.OUTPUT IMPEDANCE 200 ohms SE, 400 ohms balanced. Recommended load 50K-100K ohms and 100pF. (10K ohms minimum and 2000pF maximum).MAXIMUM INPUT 250mV RMS at 1kHz (680 mV RMS at10kHz).RATED OUTPUTS 0.5V RMS 10Hz to 20kHz, 100K ohm load (output capability is 80V RMS BAL output at 1/2% THD at1kHz, 40V SE).POWER SUPPLIESElectronically regulated low and high voltage supplies. Automatic 40 sec. warm-up/brown-out mute. Line regulation better than .01%.NOISE0.22uV equivalent input noise, IHF weighted, shorted(Low Gain) input (73 dB below 1mV 1kHz input). 0.055uV equivalent input noise (High Gain) (65dB below 0.1mV 1kHz input).TUBE COMPLEMENT (8)-6H30P dual triodes, plus (2 each) 6550C and 6H30P in power supply.POWER REQUIREMENTS100-135VAC 60Hz (200-270VAC 50/60Hz) 235 watts maximum. Standby 0.8 watts.DIMENSIONS Width 19” (48 cm); Height 7” (17.8 cm) (standard rack panel).Check out my other listings.Feel free to ask any questions.I ship items only to buyers with signature required on items above $750.NOTE: Returns not accepted.