audio research
DUAL 50

Description
Tube stereo power amplifier. Generally marked 'Electronic Industries'.

Introduced
1969 (10-07-1969)

Discontinued
1973

Revisions
DUAL 50R-1 (12-04-1969)
DUAL 50R-2 (12-17-1969)
DUAL 50A (06-05-1970)
DUAL 50B (07-11-1970)
DUAL 50C
DUAL 50D (02-04-1971)
DUAL 50D-1 (05-10-1971)
DUAL 50E (06-22-1971)
DUAL 50F (07-26-1971)
DUAL 50F-1A (?)
DUAL 50F-1B (12-08-1971)
DUAL 50G

Options
-

MSRP (US new retail)
$440 (DUAL 50A/DUAL 50B)
$540 (DUAL 50B Unity Damping)

Specifications

Power output 50 watts RMS 30Hz/15kHz per channel
Power bandwidth  
Frequency response ± 1 dB 25Hz/20kHz @ 50W RMS
Input sensitivity 1.15V RMS for 50W RMS output
Input impedance 500kOhms
Output taps 4, 8 and 16 ohms
Output regulation  
Overall negative feedback  
Damping factor Approximately 14 to 1kHz
Distortion Less than .1% 1kHz/50W RMS
Slew rate  
Rise time Approximately 20µs
Hum & noise 90dB below rated output
Power supply energy storage  
Power requirements 117V 50/60Hz, approximately 200 watts at idle, approximately 325 watts at full power
Tube complement (2 matched pairs) GE6L6/KT-66/EL34, (3) 12AX7, (2) QA2, (4) 6FQ7
Other  
Dimensions 16" W x 9 1/4" D x 7 1/2" H
Weight 38 lbs. Net, 45 lbs. Shipping

Reviews

Pictures

DUAL 50:

DUAL 50A:

DUAL 50F-1B: