Marantz PM-300 amplifier

The Marantz PM-300 is a stereo amplifier that is FTC rated for 4 ohms at 37 watts per channel, 20 Hz to 20 kHz, at no more than 0,08% Total Harmonic Distortion. At the usual speaker impedance of 8 ohms the rated FTC output power was 30 watts per channel. Overall, this is a nice, moderate cost unit suitable for smaller installations. The output power meters, though having essentially a flat frequency response, had acceptably accurate readings only when the output power was 6 watts 8 ohms, or higher. The meters are calibrated from 0 to 60 watts into 8 ohms and from 0 to 120 watts into 4 ohms. Its equalization of 50 Hz; 1,000 Hz and 10,000 Hz. There is also a 20 Hz low filter. Another convenience feature is the single switched and unswitched AC outlets. In our specifications we show the power output measured into an 8 Ω load to be 3 watts more than the manufactures claimed rating. Marantz emphasises the 4 Ω rating because they say speaker impedances are usually 5-6 ohms, not 8 ohms.

Specifications:

Power Output Rating per Channel:

37 W at 4 Ω RMS

33 W at 8 Ω RMS

Total Harmonic Distortion (at RMS 8 Ω):  0,025%

Intermodulation Distortion:  0,03%

Damping Factor:  60 (8 Ω , 1 kHz)

Frequency Response:  15 Hz - 50 kHz

Signal-to-Noise Ratio: 

Phono :  87 dB

Line :  98  db

Input Sensitivity/ Impedance: 

Phono :  2,8 mV/47 k Ω

Line :  150 mV/ 25 k Ω

Controls:

Bass :  +12/-15 dB at 50 Hz

Mid :  +5,5/-6 dB at 10 kHz

High :  +10/-9 dB at 10 kHz

Low Filter Attenuation:  3 dB at 20 Hz

Dimensions (W x H x D):  416 x 146 x 243 mm

Weight (net):  6,2 kg