Audio Research D-80

Audio Research D-80

Valve Tube Power Amplifier

The Audio Research D-80 tube amplifier offers a wide and rich tonal palette, high resolution, and musical power in an elegant design that draws from their range of Reference tube amplifiers.

The prefix “D” has been associated with legendary Audio Research amplifiers that established the high-performance amplifier market, so this new model carries the responsibility to continue forward the classic performance and gravitas for which its ancestors are known. The D-80 delivers.

The foundation for the D-80’s design is taken directly from their Reference 80S stereo tube amplifier.

A pair of KT150s per channel are part of a fully balanced, differential signal path. Internal components were chosen to maximise tonal density, bass control, and the expansiveness of the recording space, but in a more economical form than can be achieved by the Reference 80S.

The D-80 is a full pentode design.

To maintain simplicity, and with the expectation that most listeners will pair the D-80 with a balanced preamplifier with XLR outputs, this amplifier has only balanced XLR inputs. 4-,8-, and 16-ohm speaker taps allow proper loudspeaker matching.

The output of the D-80 is fully balanced, driving both loudspeaker legs.

Auto-bias automatically adjusts the D-80’s output tube bias continuously, in real time, adjusting for line voltage and tube age, so great sound is consistent every day.

Like all Audio Research products, it is entirely built in their Minnesota facility, tested twice, and individually auditioned in their reference system.

Audio Research D-80 Specifications

Power Output:

70 watts continuous from 20Hz to 20kHz. 1kHz total harmonic distortion typically 1% at 140 watts, below 0.04% at 1 watt. (Note that actual power output is dependent upon both line voltage and “condition” i.e.: if power line has high distortion, maximum power will be affected adversely, although from a listening standpoint this is not critical)

Power Bandwidth – (-3dB points) 7Hz to 68kHz

Frequency Response – (-3dB points at 1 watt) 0.7Hz to 94kHz

Input Sensitivity – 1.4V RMS Balanced for rated output. (25.5 dB gain into 8 ohms). RMS SE for rated output.

Input Impedance – 300K ohms Balanced (75K ohms SE)

Output Polarity – Non-inverting. Balanced input pin 2+ (IEC-268)

Output Taps – 4, 8, 16 ohms

Output Regulation – Approximately 1.0dB 16 Ohm Load to Open Circuit (Damping factor approximately 8)

Overall Negative Feedback – 15dB

Slew Rate – 10 volts/microsecond

Rise Time – 4.0 microseconds

Power Requirements – 105-130VAC 60Hz (210-250VAC 50Hz) 420 watts at rated output. 221 watts at “idle”, 3.6 watts off Units for Japan: 100VAC 50/60Hz

Tubes Required – 2 matched pair KT150 (Power output V1-V4); 2 6H30 (Gain stage V5, V6)

Dimensions – Width 18.5” (47 cm) chassis; 19.0” (48.26 cm) faceplate, Height 10.5” (26 cm), Depth 18.5” (47 cm). With handles & connectors: 21” (53.3 cm)

Weight – 62 lbs. (28.2 kg) Net; 73 lbs. (32.7 kg) Shipping