Description: Tubed, fully balanced class-AB mono amplifier with 20A IEC connector, autobias, fan-speed control, tube hour meter, and monitor. Tube complement: Three matched pairs KT170 (Power Output positions V1-6), two 6H30 (Gain stage V7 and regulator driver V10), one 12AX7/ECC83 (Gain stage V8), and one 6550 (Regulator V9). Inputs: One pair XLR (balanced), 1 pair RCA (single-ended). Outputs: 4 and 8 ohm. Power output: 330W @ 1kHz 0.92% THD+N 10Hz–80kHz unweighted; 1W @ 1kHz 0.013% THD+N 10Hz–80kHz unweighted. Frequency response: (–3dB points at 1W) 5Hz–99.5kHz. Input sensitivity: 2.48V RMS Balanced for rated output; 1.23V RMS single-ended for rated output; 135mV RMS Balanced for 1W output; 70mV RMS for SE input for 1W output. Gain: 26.3dB balanced input into 8 ohms; 34dB single-ended input into 8 ohms. Input impedance: 200k ohms balanced, 36k ohms single-ended. Output polarity: Noninverting. Balanced input pin 2+ (IEC-268). Output regulation: 0.82dB 8 ohm load to open circuit. Output impedance: 0.812 ohms. Damping factor: 10 at 8 ohms. Noise: (Input shorted, noise level referenced to 1W into 8 ohms) Balanced –80dBV, 10Hz–80kHz Unweighted, –91dBV 10Hz–80kHz A-weighted. Single-ended –75dBV 10Hz–80kHz Unweighted, –86.5dBV 10Hz–80kHz A-weighted. Power requirements: 105–130VAC 60Hz (210–250VAC 50Hz) 987Wpc maximum draw at rated output, 386W at "idle," when amplifier is on but nothing is playing, 1.1W in "standby" when amp is plugged in but powered off.Dimensions: 19" (463mm) W × 21.5" (546mm) D × 10.25" (260mm) H. Weight: 101lb (49.5kg).
Finish: Natural silver or black anodized.
Serial number of units reviewed: 056438, 056439. Designed and built in Minneapolis, Minnesota.
Price: $90,000/pair. Approximate number of US dealers: 40. Warranty: 3 years on product, 90 days on tubes.
Manufacturer: Audio Research, 6655 Wedgwood Rd. N Suite 115, Maple Grove, MN 5531. Tel: (763) 577-9700. Email: service@audioresearch.com. Web: audioresearch.com.
