Denon PMA-1090 (1992)

Name: Denon PMA-1090
Brand: Denon

The Denon PMA-1090 is a heavy integrated amplifier from 1992. It came in two versions: the standard black PMA-1090 and the PMA-1090G, a gold-faced model with wood side panels. The black one was priced at ¥99,000 and the gold with wood at ¥106,000.

The headline feature is the "MOS super optical Class A" output stage. It is Denon's evolution of its Super Optical Class A circuit, with MOSFETs added to the driver stage via an inverted Darlington configuration. The power supply uses a large toroidal transformer. The preamp and power amp sections are fully independent, each with its own supply. Even the left and right channels in the power section are separate circuits. The aim is channel separation and minimal mutual interference, and the signal path from input to speaker terminals is kept as short as possible.

The specs are big: 150W + 150W into 8Ω, and 180W + 180W into 6Ω, with dynamic power rated at 350W into 4Ω and 450W into 2Ω. Distortion is rated at 0.004% (1kHz, 75W, 8Ω). Line input frequency response runs from 4Hz to 150kHz. The preamp section has a phono stage switchable for MM and MC cartridges, a source direct switch that bypasses tone controls, loudness, and subsonic filtering, and a CD balance (XLR) input. It also has a low-impedance volume control to keep the signal-to-noise ratio high at listening levels. The standard version weighs 17.5kg (19kg for the G), so it's built like a tank. The 100V power supply confirms it was intended for the Japanese market.

Documentation on this model is thin. No service manual has surfaced in the usual archives, and most of what's known comes from Japanese spec databases and Russian-language seller listings. One drive2.ru article groups it with the PMA-560, 860, 1060, and 1560, and suggests it may be a "clone" of the PMA-1560. That is the author's speculation, not confirmed fact. The same source notes it's part of Denon's "Japanese" line, distinct from the European-market PMA series.

Modern sellers like it. Listings describe it as rare, powerful, and particularly suited to jazz and blues, and one owner praises "crystal highs and very impressive bass even at low volume." Current asking prices in Russian listings range from about 54,000 to 110,000 rubles, with the gold G version commanding a premium.