Marantz - PM-94 Solid state integrated amplifier

Marantz PM-94
Integrated stereo amplifier Quarter A (1985-90)
A beautiful amplifier that produces a wonderful sound.
Main preamplifier with Marantz's separate amplification technology.

The output stage is a triple push-pull configuration with MOSFETs.
The MOSFET features characteristics such as 'excellent high-frequency performance, high breakdown voltage, and high power handling, all achievable simultaneously', 'since it operates only with majority carriers, in principle it yields a high input impedance, higher than that of a J-FET', and 'since during switching there is a reduced storage effect, the turn-off time is extremely short and high-speed switching is possible'. Together with Marantz's original Quarter A, the MOSFET achieves ideal operation.

Using an exclusive Quarter-A circuit, it operates in Class A mode fully up to one-quarter of the maximum output power and automatically switches to Class AB operation up to the maximum power. This autoshift is controlled by electronic control. It detects the output voltage of the main amplifier and controls the bias current with a high-speed switching circuit.
The detection speed of the PM-94 circuit is higher than that of the conventional Quarter A circuit, enabling smoother control.

To fully demonstrate the performance of the MC cartridge, two high-performance MC transformers are independently mounted at the MC input, on the left and right sides.
This transformer has a two-winding configuration and uses dual shielding in the core and winding directions. It offers a quality comparable to that of the high-sound MC transformer "MC1000".
The increment ratio can be switched between High and Low.



The power supply section is equipped with a large transformer and a large electrolytic capacitor of 90,000 μF.
In particular, toroidal transformers are shielded by three layers of silicon steel plates to prevent flux.

The copper-coated steel sheet material “Copper-Tight” is used throughout the frame, and Copper-Tight’s uniform copper finish is more effective than traditional copper plating.

A careful tuning has been applied, for example by using components that have undergone auditory testing.
We have adopted a pair of electrolytic capacitors with equivalent characteristics and sound quality, and switches with improved sound quality thanks to copper plating. In addition, 70-micron-thick printed circuit boards and oxygen-free copper wires are used.
In addition, to prevent any degradation in sound quality caused by soldering, the capacitor is secured with screws, and all screws are tin-plated.

Equipped with a direct CD position. In this position, the input selector is connected directly to the flat amplifier, bypassing a stage such as an input selector or a tape monitor. Furthermore, since the flat amplifier has a FET input, the variation in input impedance is almost negligible even with changes in the master volume resistance.

Thanks to the HiFiVCR’s monitor position, you can play music through the HiFiVCR with the same feel as a tape monitor.

Marantz PM-94
Description:
The PM-94 is a heavyweight classic integrated amplifier from the 1980s that used Marantz's 'Quad A' topology, in which the Class A circuit switched to AB when high output levels were required.

Specifications
Output power: 140 watts per channel into 8 Ω (stereo)

Frequency response: from 10 Hz to 100 kHz

Total harmonic distortion: 0.01%

Damping factor: 200

Input sensitivity: 250 mV (MC), 2.5 mV (MM), 150 mV (line)

Signal-to-noise ratio: 92 dB (MM), 98 dB (line)

Output: 465 mV (line), 1.5 V (Pre output)

Dimensions: 465 x 146 x 410 mm

Weight: 23 kg

Year: 1991

Approximate original price: 228,000 Yen (Japan, 1985), 3,000 DM

Please make sure the photos are part of the description.

The shipping costs are higher given the weight of the object.