The Marantz PM-5 amplifier is a versatile, high-quality component from Marantz’s Esotec series, known for its robust design and impressive audio performance. Produced from 1979 to 1983, this amp supports both Class A and Class AB operation.
In Class A mode, it delivers 20 watts per channel at 8 ohms, while in Class AB, it provides 80 watts per channel at 8 ohms. Its total harmonic distortion (THD) is a low 0.015%, ensuring clarity even at high volumes.
The PM-5 features a direct-coupled (DC) design that minimizes transient intermodulation distortion (TIM), resulting in clean, accurate sound. It incorporates a push-pull configuration and uses high-speed transistors with a 90 MHz cutoff, reducing switching distortion in Class AB mode. The unit includes two phono inputs with support for both moving magnet (MM) and moving coil (MC) cartridges, offering flexibility for vinyl enthusiasts. It also includes an adjustable tone control, balance adjustment for each channel, and a loudness feature to enhance bass and treble at low volumes.
The amp is housed in a durable metal case with optional wooden cabinet add-ons and weighs approximately 13 kg. Other thoughtful design elements include a peak power meter on the front panel and a dual speaker output that allows for comparisons between two sets of speakers. This amplifier also features a high signal-to-noise ratio, making it ideal for high-fidelity listening. Overall, the PM-5’s design, flexibility, and sound quality have made it a valued component among audiophiles and vintage hi-fi enthusiasts.
While the Esotec line was primarily aimed at the Japanese and European markets, it is known for being relatively rare in the U.S., which has contributed to its allure and collectibility today. These pieces are recognized not only for their audio performance but also for their visual appeal, with a sleek and often understated aesthetic that continues to attract vintage audio collectors and audiophiles alike.
For those seeking more detailed discussions and community insights on the Marantz Esotec series, forums like Audiokarma have threads dedicated to user experiences and technical observations, where enthusiasts share their appreciation for this iconic line’s legacy in high-fidelity audio equipment.
Marantz PM-5 / Pre-Main Integrated Amplifier ( Class A / AB) / Esotec Series
The Marantz PM-5 Pre-main amplifier is capable of switching between pure class A and class AB.
In addition to pure A-class 20W/ch, AB-class 80W/ch can be switched. Moreover, in order to raise the quality of AB-class to the level of pure A-class, a high-speed high-fT transistor with a high cut-off frequency of 90 MHz is adopted in the power stage, eliminating the switching distortion that is a defect of AB-class to the limit.
The PM-5 adopts a complete push-pull DC amplifier configuration in all stages to eliminate TIM distortion from every corner of the amplifier, thereby improving the bare characteristics.
Transient cross-modulation distortion and static characteristics are improved without applying a large amount of NFB.
In order to improve the stable operation of the power transistor, a newly developed heat pipe system has been adopted for the heat radiation mechanism. Since heat is out of the circuit and cooled by a radiator, the transistor can be placed in an ideal position, simplifying the circuit and reducing distortion.
The power supply section is equipped with a large-capacity capacitor developed for audio equipment and a compact high-power transformer filled with a special resin for heat resistance.
The phono amplifier block is designed with low distortion and high S/N ratio by using transistors lavishly.
In addition, a straight DC circuit connecting the phono amplifier directly to the power stage is incorporated to improve the quality of disc playback.In addition, the phono amplifier incorporates a high-precision MC head amplifier and subsonic circuit. The subsonic function works only for the equalizer to simplify other functions.
The tone control is adjustable by ± 8 dB from 100 Hz to 10 kHz. The balance can be adjusted independently on the left and right sides. Moreover, the use of high precision volume realizes a flat response at the midpoint of the knob.
It is also equipped with a loudness control that compensates for the low and high frequencies.
The center of the front panel is equipped with a full-scale peak power meter. Unlike bar display, both pure A class and AB class LED display power as points, so clear and accurate output can be directly read.Under the meter, there are various functions such as a dubbing circuit that enables mutual recording from deck to deck, and a speaker selector switch that enables listening comparison between two speakers and simultaneous playback.