Audio Research is one of the most dependable brand names when it comes to high-end audio systems. For years the brand has been recognized by audiophiles throughout the world as equipment that delivers clear and consistent quality in music.

What are the specs for the Audio Research D-79?

Power Output:
75 watts per channel minimum RMS (both channels operating) at 16 ohms from 30Hz to 15kHz with less than 1% THD. (Typically approximately .1% (D-79B/C: .06%) at rated power in midband) Approximate actual power available per channel at “clipping“ (Both CH. OP, 1kHz): 87 Watts.
Power Bandwidth:
(-3dB points) 15Hz and 40kHz
Frequency Response:
Input Sensitivity:
.75 V RMS for rated output
Input Impedance:
D-79: 80K ohms, nominal. D-79B/C: 75K ohms, nominal.
Output Taps:
Output Regulation:
D-79: Approximately 1.5dB, 16 ohm load to open circuit. D-79B/C: Approximately .6dB, 16 ohm load to open circuit
Overall Negative Feedback:
D-79: 13.5dB. D-79B: 18.5dB. D-79C: 21dB
Damping Factor:
D-79: Approximately 8. D-79B/C: Approximately 15
Intermodulation distortion: Less than .5% at 1dB below rated output (90V p to p, 16 ohms) (SMPTE method)
Slew Rate:
Approximately 10 V/µs
Rise Time:
5 µs
Hum & Noise:
Wideband, unweighted, more than 90dB below rated output. Line components, more than 80dB below rated output.
Power Supply Energy Storage:
Power Requirements:
105-125/210-250 VAC, 50/60Hz, 750 watts maximum, 350 watts at “idle“, 550 watts at rated power
Tube Complement:
D-79: (6) ECC83/12AX7, (8) 6FQ7, (2 matched pairs) 6550, (1) 6550. D-79B: (1) 6922, (4) 12AX7,(2) 6FQ7, (2 matched pairs) 6550,(1) 6550, (1) 12BH7. D-79C: (9) 6922, (2 matched pairs) 6550 (1) 6550, (1) 12AT7, (1) 12BH7. D-79C MKII: (3) 6922, (6) 6FQ7, (2 matched pairs) 6550, (1) 6550, (1) 12AT7, (1) 12BH7
19“ (48 cm) W (standard rack panel) x 10 ½“ (26.5 cm) H x 17 ¼“ D (front panel back). Handles extend 1 5/8“ (4.1 cm) forward of front panel.
85 lbs. (38.8 kg) Net, 100 lbs. (45.7 kg) Shipping.

What else to know about the Audio Research D-79?

The Audio Research D-79 first appeared in 1979. The unit is a pentode operated in ultralinear, with a huge power supply. The first series of 79's were not noted as an 'A' but are called 'A'. The 'A' version was similar to D76A front end with this power supply, the 'B' was designed with the D90 front end and the 'C' is designed around the D115 (and D115 MKII on the 79C-MKII). They are very well built and can deliver top performance with very little maintenance. One thing to keep one thing in mind is that Audio Research amps work best with top quality tubes.\ \ The Audio Research D-79 was conceived in response to demand from and for audio perfectionists. While it is not necessarily the "ultimate" amplifier, and will not provide its intrinsic performance with all speaker systems, it will provide a new standard of 'High Definition' reproduction of music within its power capability throughout much of the audio range when used with suitable speaker systems. Some of its features include near military components and construction with unsurpassed accessability for maintenance. Three built-in fans provide forced air cooling of the output stage for extended tube and component life. A high energy, well regulated power supply with Audio Research's balanced and cross-coupled(patented) circuitry is employed together with other Audio Research technologies to provide an incredibly stable amplifier capable of sorting out and properly defininf the most subtle nuances of sound even with the most reactive of modern speaker loads. To obtain the best performance from this amplifier, it is recommended that a commensurate quality preamplifier such as the SP-6A be used.

Brief History of Audio Research

Other Audio Research Products We Often Buy

Typically, StereoBuyers purchases mostly used amplifiers, especially the vintage amps and high-end Audio Research models.

StereoBuyers has purchased tens of thousands worth Audio Research brand equipment since 2014, with individual buys ranging from $100 to well over $50,000. If you are moving, ready to upgrade, or have Audio Research equipment you do not or will not be using, why not contact us today to find out if it is worth good money?

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The following images show actual Audio Research equipment purchased by StereoBuyers.