The MF2250 and the MF2500 offered audiophiles a choice of power level in stereo amplifiers while the MF5600 was a five-channel amplifier.

The overall circuits in these amplifiers used a combination of FETs, and bi-polar transistors. FETs were chosen for the gain stage because like tubes and unlike bipolars, they produce almost no strident odd-order harmonics. Bi-polar devices were specified for the output stages of these amplifiers for their low output impedance, resulting in improved bass response.

Specifications:
Power Output: MF2250 - 120 watts per channel; MF2500 – 240 watts per channel; MF5600 – 120 watts per channel for all five channels. All deliver their power from 20Hz to 20KHz at no more than 1% THD and IM, both channels driven into 8 ohms.
Distortion: less than .1% THD or IMD
Response: bandpass 20Hz to more than 20kHz , +0, -.5dB
Hum & Noise: 100 dB relative to max output
Mechanical:  MF2250 - 19" X 4 ¼ " X 16”, MF2500  19” X 6 ¾” X 16”, MF5600 19” X 8” X 16”