Recently traded in excellent condition and full working order. A wonderful sounding pre- amp. Unit in mint condition, has Phono Stage. Serial number 99037003.
Please see our listing for the matching Audio research Classic 60 Power amp here
Specifications:
Frequency response High Level Section: ±.5dB, 5 Hz to 50 kHz, - 3dB points below 1 Hz and above 200kHz.
Phono: ±.3dB of RIAA, 30Hz to 40kHz.
Distortion (THD): Less than 0.1% at 2V RMS output. (Typically less than 0.005% in midband)
(SP-9: < .01% @ 2V RMS output 10Hz to 30kHz )
Noise & hum High Level: (1) 70 µV RMS maximum residual unweighted wideband noise at main output with gain control minimum (98 dB below 5V RMS output). (2) More than 100dB below 1 V RMS input (less than 7µV equivalent input noise)
(SP-9: Phono IHF weighted 72 dB below 1 mV input)
Phono: 0.12 µV equivalent input noise; IHF weighted, shorted input (78dB below 1 mV input).
Gain Phono input to tape output: 46dB
Phono input to main output: 67dB (SP-9: Phono 66dB (RIAA ±.25 dB)
High level inputs to tape output: 0dB
High level inputs to main output: 21dB
CD input to main output: 9 dB
Input impedance: 50 k ohms line inputs
47 K phono (Phono provisions for any value below 47K ohms or added input capacitance for matching certain magnetic cartridges)
Output impedance: 250 ohms main output
850 ohms recorder output
Recommended load: 60K ohms and 100pF. (20K ohms minimum)
Output polarity
Maximum inputs: Phono, 200 mv at 1kHz (1000 mv RMS, 10kHz)
High level inputs essentially overload proof
Rated outputs: 2 V RMS 5 kHz to 50 kHz, all out-puts; 60k ohm load (main output capability is 50 V RMS output at 0.5% THD at 1 kHz into a 100K ohm load with 5V RMS high level input)
Power supplies: Electronically–regulated low and high voltage supplies and electronic decoupling. Shielded toroid transformer. Line Regulation better than .01%.
Tube complement: (2) 6922
Power requirements
Dimensions: 19” (48 cm) W x 5 1/4” (13.4 cm) H (standard rack panel) x 10 ¼” (26 cm) D. Handles extend 1 ½” (3.8 cm) forward of the front panel. Rear chassis fittings extend 7/8” (2.3 cm).
Weight: 12 lbs. (5.5 kg) Net; 21 lbs. (9.5 kg) Shipping
