Pioneer - M90a Solid state integrated amplifier

This well-performing Pioneer M-90a power amplifier is a legendary apparition from Pioneer’s "Reference Elite" era (late 1980s, early 1990s). It is the enhanced successor to the original M-90 and is renowned for its enormous reserves, the iconic "Urushi" lacquer finish, and a sound reproduction that is both powerful and refined.
The Urushi Powerhouse:
The Pioneer M-90a is a stereo power amplifier built to the highest standards of Japan’s hi-fi heyday. The design is immediately recognizable by the deep black, glossy piano lacquer (Urushi) and the large amber digital power meters.
Key Features:
- Non-Switching Type III Circuit: Pioneer’s own technology that eliminates distortion and provides the thermal stability of transistors, allowing the amplifier to perform with Class A purity, but with the efficiency of Class B.
- Dual-Mono Construction: To maximize channel separation and minimize interference, the amplifier is internally strictly separated with two huge transformers.
- Construction:
The chassis is built extremely rigid with a honeycomb structure to counteract vibrations. The gold-plated connectors and high-quality capacitors emphasize the high-end character.
- Versatility:
The M-90a has three inputs (CD Direct, Line and Control Amp) with individual volume control, which means it can also be used without a preamplifier for a shorter signal path.

- Technical Specifications:
The M-90a is renowned for its ability to drive even the most demanding speakers (low impedance) effortlessly.
* Continuous Power (8 Ohms): 2 x 200 Watts (20 Hz - 20 kHz)
* Continuous Power (4 Ohms): 2 x 300 Watts
* Dynamic Power: 300W (8 Ohms) / 550W (4 Ohms) / 800W (2 Ohms)
* Total Harmonic Distortion (THD): 0.003%
* Frequency Range: 5 Hz to 150 kHz (+0dB, -3dB)
* Damping Factor: 125 (8 Ohms, 20 Hz - 20 kHz)
* Signal-to-Noise Ratio: 125 dB
* Input Sensitivity: 1V / 50 kOhm
* Power Consumption: 1300 Watts (maximum)
* Dimensions (W x H x D): 457 x 163 x 432 mm
* Weight: 28.0 kg

Appearance:
In nice condition, with some minor signs of use, but they are not really noticeable. See also photos.

Note for enthusiasts: Although the M-90 and M-90a look very similar on the outside, the M-90a features internal circuit and power supply improvements, resulting in an even lower noise floor and better control of the bass than its predecessor.

Warranty:
Our audio equipment generally consists of vintage gear 40 years old or older. Each unit is carefully checked by us, professionally cleaned, and extensively tested before being offered for sale.

Despite this careful inspection, it can happen that a defect arises upon receipt or after some time. Because of the age of the equipment, such malfunctions can occur unexpectedly and are not within our control.

For that reason we cannot provide a warranty on vintage equipment. We understand this may be disappointing and we believe it is important to be transparent and honest about it. Of course, we do our utmost to deliver every unit in as good a condition as possible.