The flagship of the PMG Signature Series — the best power amplifier PS Audio has ever built, period. Four hundred watts into 8 ohms, doubling to 800 into 4, with 50 watts of pure Class A bias that keeps 99% of typical listening in pure Class A. Built around a state-of-the-art active power supply and Darren Myers’s low-feedback topology. Monoblock, sold as a pair. Hand built in Boulder, Colorado.

Design

The M800’s character begins with its power supply. Where a conventional amplifier leans on a heavy passive transformer, the M800 is built around a state-of-the-art active power supply that delivers current with a speed and stability no transformer-based supply can match. Around it sits Darren Myers’s low-feedback current-based topology, chosen deliberately: the less an amplifier has to correct itself, the more honestly it passes the signal through.

Application

Each M800 is a monoblock — one chassis, one channel — sold as a pair for stereo. With 800 watts into 4 ohms and the current to double down without strain, a pair will drive virtually any loudspeaker made, from sensitive horns and electrostatics to the most demanding low-impedance reference designs. There is no speaker too difficult and no room too large. If you own loudspeakers that have humbled other amplifiers, the M800 is the pairing that ends the search.

Class A Purity

Class A is the purest mode of amplification known — and the most expensive, because its transistors are always fully active and draw power continuously. The M800 carries 50 watts of pure Class A bias. Fifty. For 99% of normal listening — and nearly all music lives well within that window — the M800 never crosses a notch, never sees a discontinuity, never asks its circuitry to correct an artifact it should not have created. What you hear is the natural texture of the recording, intact.

Power is The Key

The character of an amplifier’s energy reservoir determines more about how it sounds than any other single design choice. The M800 is built on a state-of-the-art active power supply that delivers performance no traditional passive supply can match: instant transient response with no rectifier-induced noise, a vanishingly low residual noise floor, total grip on the speaker at any output level, and full continuous output without sag.

The PMG Disappears into the Music

The M800 is built on the philosophy of strikingly low overall feedback. Because its output stage is already extraordinarily linear on its own — running deep in pure Class A, where correction is barely needed — the M800 does not have to lean on a heavy feedback loop to clean up after itself. What this produces is the M800’s defining quality: it disappears. The electronics stop announcing themselves, and what remains is the performance — 800 watts of authority, delivered with the openness of a far smaller amplifier.

Specifications

• Power Output (per monoblock): 400W into 8Ω, 800W into 4Ω, 1200W into 2Ω (1kHz, <1% THD)
• Class A Power Output: 60W into 8Ω (50W pure Class A bias)
• Frequency Response: <10Hz – 80kHz (±0.25dB)
• Input Impedance: 100kΩ SE; 200kΩ balanced
• Bandwidth: >500kHz · THD: <0.002% typical · Damping Factor: >300 at 8Ω
• Inputs: RCA 1 pair, XLR 1 pair · Speaker Outputs: 2 pair · Gain 26.2dB · Sensitivity 2.8V
• Colors: Silver or Black · Power: Auto 120/230VAC 50/60Hz · Idle 360W
• Weight: 95.7 lbs (43.4 kg) each · Dimensions: 26.75″L × 17.5″W × 8″H