I’ve been very busy repairing and restoring this stunning Marantz PM-8 integrated amplifier.
The Marantz PM-8 integrated amplifier is one of very the amplifiers from the golden era of serious hi-fi equipment. These amplifiers are monsters, massively powerful and massively heavy. They are also massively complex to work on and this one had a massive fault!
Marantz PM-8 Specifications
Power output: 150 watts per channel into 8Ω (stereo)
Frequency response: 5Hz to 100kHz
Total harmonic distortion: 0.01%
Damping factor: 100
Input sensitivity: 0.2mV (MC), 2mV (MM), 150mV (line)
Output: 150mV (line)
Speaker load impedance: 4Ω (minimum)
Dimensions: 416 x 146 x 437mm
More photos and details of the Marantz PM-8 restoration soon. You can find my article about the exploded filter capacitors, here! In the meantime, here’s a video summary of the testing and setup of bias, DC offset and power supply voltage.