Description
Tube stereo power amplifier.
Introduced
1979
Discontinued
?
Revisions
D-79A
D-79B (1980?) (Only 80 made)
D-79C (Around 25-30 made)
D-79C MKII
Options
-
MSRP (US new retail)
D-79: $3,250. Later increased to $3,700
D-79B: $4,450
Specifications
| 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-79C: .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-79C: 75K ohms, nominal | |
| Output taps | |
| Output regulation | D-79: Approximately 1.5dB, 16 ohm load to open circuit |
| D-79C: Approximately .6dB, 16 ohm load to open circuit | |
| Overall negative feedback | D-79: 13.5dB |
| D-79C: 18.5dB | |
| Damping factor | D-79: Approximately 8 |
| D-79C: Approximately 15 | |
| Distortion | 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)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 | |
| Other | |
| Dimensions | 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. |
| Weight | D-79: 89 lbs. (41 kg) Net, 107 lbs. (49 kg) Shipping |
| D-79C: 85 lbs. (38.8 kg) Net, 100 lbs. (45.7 kg) Shipping |
Reviews
Number 18 (D-79: Full Review), Number 25
(D-79B: Full Review), Number 26 (D-79B: Further Thoughts)Pictures
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D-79B:
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D-79C:
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