Audio Research Dual 75 / D75 // Vintage Stereo Tube Amplifier

The Audio Research Dual 75 is a vintage tube amplifier that holds a revered place in the history of high-end audio. Introduced in the early 1970s, the Dual 75 was one of Audio Research's landmark designs, showcasing the company's innovative approach to blending tube warmth with modern clarity and control. It’s a 75-watt-per-channel stereo power amplifier, designed to bring dynamic, transparent, and lifelike sound to audiophiles looking to elevate their systems.

Even decades after its release, the Dual 75 remains a benchmark for those who appreciate the emotional depth of tube amplification paired with high fidelity performance. Its robust build quality and timeless sound have earned it a dedicated following among collectors and enthusiasts.

Production

1971-72

Condition

9/10

Serial No.

271111-7

Orig. MSRP

$975

Restoration

• Replaced 6550 output tubes in left channel
• Burnished internal switches for bias jacks
• Cleaned control contacts
• Adjusted bias
• Verified power and distortion Both channels 75 watts per channel RMS into 8 ohms @ less than 1% THD
• Replaced all electrolytic capacitors

Factory Specs

Power output 75 watts per channel into 8Ω (stereo)

Frequency response 15Hz to 30kHz

Total harmonic distortion 1%

Damping factor 14

Input sensitivity 1.5V

Signal to noise ratio 80dB

Speaker load impedance 4Ω to 16Ω

Valve complement 4 x 12AX7, 8 x 6FQ7, 2 x 6550, 1 x 5881

Dimensions 19 x 7 x 12.25 inches

Weight 52lbs

Documentation

Audio Research Dual 75 Owner's Manual

The History of Audio Research

Audio Research Corporation, affectionately known to fans as ARC, was founded by William Z. Johnson, who began designing custom audio electronics in the early 1950’s and who also operated a specialty audio retail store until the mid-1960’s. Johnson’s efforts almost single-handedly revived vacuum-tube designs at a time...
[ Read More ]

Liner Notes

The DUAL 75 Amplifier is a basic power amplifier of near-military construction aimed at advancing the art of music reproduction. Its dynamic characteristics are without equal when used with commensurate associated equipment.

Stock No.

8858363429085