Tube mono power amplifier. Remake of Dynaco Mark III reusing only the transformers. Generally marked 'Electronic Industries'.
The M-60A and M-60B were offered at the same time, where the M-60A was the same as M-60B except with additional provision for regulated 75 Volt 20 ma. supply for FET preamplifier or other application.
M-60B-2 - Serial numbers are usually around 074220.
M-60B-2R - Serial numbers are usually around 175220. This model is unusual in that it has 2 extra holes in the chassis for some extra tubes that were not incorporated in the final production of this amp. This amp also has a standard AC outlet on the top of the chassis which the other versions of the M-60 amplifier lacked.
M-60D - ARC and Fulton musical industries (FMI) had an agreement that FMI could modify the M-60 and sell it with the FMI logo as the M-60D amplifier.
3/16" gray anodized aluminum rack panel (19" W x 10 1/2" H) with cutouts for Rotron fans, together with 1/8" anodized aluminum mounting frame kit for mounting 1 or 2 M-60A or M-60B ($100)
MSRP (US new retail)
|Power output||50 Watts RMS 20Hz/20kHz|
|Frequency response||± 1 dB 20Hz/20kHz|
|Input sensitivity||1.15V RMS for 50 W RMS output|
|Input impedance||500K ohms|
|Output taps||4-8-16 ohms|
|Overall negative feedback|
|Distortion||Less than 1% 30Hz/20kHz @ 50 Watts|
|Rise time||Approximately 20 µs.|
|Hum & noise||90dB below rated output|
|Power supply energy storage|
|Power requirements||117V 50/60 Hz, approx. 150 Watts at idle, approx. 200 Watts at rated power|
|Tube complement||(1) 12AX7, (2) 6FQ7, (2) 0A2, (2) 6550, (1) 5AR4|
|Other||Load regulation: Approximately 1-172 dB/1kHz|
|Dimensions||9" W x 10" D x 7" H|
|Weight||21.5 lbs. Net; 26 lbs. Shipping|