Audio Research SP9 preamplifier Specifications

Sidebar 3: Specifications

Description: hybrid (tube/FET) stereo preamplifier with one phono input, six line-level inputs, and two tape loops. Frequency response: 30Hz-40kHz ±0.3dB (RIAA phono), 5Hz-50kHz ±0.5dB (line). Distortion: <0.01% at 2V output. Input impedance: 47k ohms standard, with user-adjustable resistance and capacitance (600pF as supplied) (phono); 50k ohms (line). Output impedance: 250 ohms (main), 850 ohms (tape-out). Recommended load: 60k-100k ohms in parallel with 100pF (20k ohms minimum and 1000pF maximum). Phono stage gain: 67dB to main out, 46dB to tape-out. Phono sensitivity: 0.25mV at 1kHz for 0.5V output. Line-stage gain: 21dB to main out (CD stage 12dB lower gain), 0dB to tape out. Line sensitivity: 50mV RMS at 1kHz for 0.5V output. Output level: 2V RMS 5Hz-50kHz, all outputs into 60k ohms (maximum from main output, 50V RMS at 0.5% THD at 1kHz into a 100k ohm load with 5V RMS high-level input). Phono overload: 200mV at 1kHz (1000mV RMS, 10kHz). Maximum input level (line): essentially overload-proof. Noise: 98dB below 5V RMS output, greater than 100dB below 1V RMS input (line), 78dB below 1mV input (phono).
Dimensions: 19" W by 10?" D by 5?" H. Weight: 13 lbs.
Serial number of units auditioned: Not noted (1987); 60037003 (1990); 80437006 (1991).
Price: $1695 (1987); $1795 (1991); no longer available (2002).
Approximate number of dealers: 55.
Manufacturer: Audio Research Corporation, 3900 Annapolis Lane North, Plymouth, MN 55447-5447. Tel: (763) 577-9700. Fax: (763) 577-0323. Web: