Marantz PM-54 (1984)

Name: Marantz PM-54
Brand: Marantz

The Marantz PM-54 is a pre-main (integrated) amplifier released in 1984 at ¥62,000. It was developed alongside the PM-64 around the concept of digital compatibility. Its key design feature was AVSS - Auto Voltage Shift Supply. AVSS shifts the output supply voltage according to the power demanded, so the output stage runs at the most suitable voltage from small outputs up to maximum. That let the PM-54 realize high power while maintaining quality, and it was designed to keep delivering power even when speaker impedance momentarily dropped to very low values. A direct switch was included for higher signal-to-noise ratio and high-speed signal transmission with digital sources. The phono stage accepted both MM and MC cartridges.

Rated output was 80W + 80W into 8 ohms (20 Hz to 20 kHz) per audio-database.com (one source lists 60W per channel), with output bandwidth extending from 5 Hz to 40 kHz at 0.03% THD. Total harmonic distortion was rated at 0.015%, and so was intermodulation distortion. The damping factor was 90 into 8 ohms per audio-database.com (one source lists 100). Phono MM input sensitivity was 2.5mV/47kΩ, MC was 250µV/100Ω, and the line-level inputs (Tape, Tuner, Aux, CD) sat at 150mV/25kΩ. Signal-to-noise ratio measured 84dB (MM), 68dB (MC), and 96dB on line inputs. The unit drew 150W and weighed 8.8kg per audio-database.com (one source lists 9.5kg). An optional sidewood case, the WPM-64, was available for ¥4,000. The PM-54 uses a Class H amplifier topology, which it shared with the PM-64. The only difference between the two is the rail voltage values for the high and low supply pairs.

One owner described the PM-54 as having "the signature warm Marantz sound with solid build quality," and a forum commenter noted it sounded "only a bit short of the more expensive PM-66 KI." That comparison spans over a decade of Marantz design, though. No period magazine reviews of the PM-54 have surfaced in the archive's sources, and documentation on this model is limited to database listings and owner accounts.