audio research
D-115

Description
Tube stereo power amplifier.

Introduced
1983

Discontinued
1989

Revisions
D-115 MKII (1984)

Options
-

MSRP (US new retail)
D-115 MKII: $2,995. Later increased to $3,250 (?)

Specifications

D-115 MKII:

Power output 100 watts per channel minimum continous power (both channels operating) at 16 ohms from 20Hz to 20kHz with less than 1% total harmonic distortion (typically less than .005% at one watt) Approximate actual power available per channel at "clipping" (both ch. op., 1kHz): 110 Watts
Power bandwidth (-3dB points) 12Hz to 60kHz
Frequency response  
Input sensitivity 0.6V RMS for rated output.
Input impedance 75 kOhms, nominal
Output taps  
Output regulation Approximately 0.5dB, 16 ohm load to open circuit.
Overall negative feedback 19.5 dB
Damping factor Approximately 17
Distortion Intermodulation distortion: Less than 0.1% at 1dB below rated output (100V p to p, 16 ohms - SMPTE method).
Slew rate 15 V/µs
Rise time 5 µs
Hum & noise 90dB below rated output - less than 2mV RMS - (Broad-bandwidth unweighted, inputs shorted)
Power supply energy storage 280 joules
Power requirements 105-125VAC 60Hz (210-250VAC 50Hz) 1000 watts maximum, 400 watts at "idle".
Tube complement D-115: (7) 6922, (4 matched pairs) 6550, (1) 6550, (1) 12AT7
  D-115 MKII: (3) 6922, (4) 6FQ7, (4 matched pairs) 6550, (1) 6550, (1) 12AT7
Other  
Dimensions 19" (48 cm) W (standard rack panel) x 7" (18 cm) H x 16.5" (42 cm) D (front panel back). Handles extend 1 5/8" (4.1 cm) forward of the front panel.
Weight 68 lbs. (31 kg) Net; 84 lbs. (38 kg) Shipping

Reviews

Issue 41 (D-115 MKII: Full Review)

Pictures

D-115:

D-115 MKII: