REF 610T

About the REF 610T

The Audio Research REF 610T is a high-end monoblock power amplifier featuring a fully balanced, push-pull tube design with sixteen 6550C pentode output tubes arranged in matched pairs, plus two additional 6550Cs as driver tubes. The input gain stage uses twin 6N1P triodes and a 6H30 follower. It delivers 600 watts continuous power from 20Hz to 20kHz into 4, 8, or 16 ohms, with a frequency response from 1Hz to 200kHz and a total harmonic distortion typically 0.5% at full power. The amplifier includes a vacuum-fluorescent display showing tube bias, AC line voltage, power output, and tube hours, with bias adjustment simplified to only the first two output tubes. The chassis weighs about 170 pounds and uses silent convection cooling, with an optional fan available. It requires dedicated 20- or 30-amp power lines due to its high power consumption (up to 2300 watts max). The REF 610T is known for its neutral tonal balance, extended frequency response, and elimination of typical tube amplifier coloration, making it a reference-level amplifier for audiophiles. It has balanced inputs only and a gain of 24 dB.