PS Audio PMG Signature Series S400 and S200 Power Amplifiers

All Image Credit: PS Audio

PS Audio from Bolder, Colorado announces the introduction of its PMG Signature Series S400 and S200 stereo power amplifiers. Both models are single-chassis stereo power amplifiers intended for high-performance two-channel audio systems. They join the PS Audio PMG Signature series, created in 2025 to celebrate the American HiFi brand’s 50^th anniversary. The S200 delivering 100 watts into 8 ohms and the S400 providing 200 watts into 8 ohms. Both designs operate in pure Class A bias for their initial output, with the S400 running in Class A for the first five watts and the S200 for the first ten watts. According to PS Audio, this is intended to optimise performance during the lower power levels. Both models are available in either a black or silver finish.

Both amplifiers employ very low feedback and offer ultrawide bandwidth to beyond 500 KHz with a slew rate of 200 volts per microsecond. All helping ensure fast transient response and very low distortion across the entire frequency range. The S400 places two complete PMG Signature channels of amplification in a single chassis, while the S200 uses a single design intended to minimise crosstalk between its left and right channels.

Both amplifiers use an active power supply, which supports cleaner power and greater current on demand than conventional transformer-based designs. The frequency response of both models is specified at <10Hz – 80KHz (±0.25dB), with a measured performance that is excellent, showing a 10 KHz square wave with no overshoot or ringing.

10KHz Square Wave

Both models provide the same rear panel connectivity that supports; 1 x XLR and RCA selectable line level inputs, 2 x stereo speaker binding posts enable bi-wiring, and 1 x left and right subwoofer output. A 3.5mm 12 VDC trigger I/O is provided for use with custom-installation audio and home theater systems.

Features At A Glance:

S400

• Audio Inputs: RCA (Single-ended): 1 pair  |  XLR (Balanced): 1 pair
• Speaker Outputs: Silver Plated Binding Posts: 4 pair
• Trigger Input: 3.5mm, 5–15VDC  |  Output: 3.5mm, 12VDC
• Gain: 26.2 dB
• Sensitivity: 2.0V
• Power Output: 200W/ch into 8Ω, 400W/ch into 4Ω (1KHz, <1% THD)
• Class A Power Output: 5W/ch into 8Ω
• Frequency Response: <10Hz – 80KHz (±0.25dB)
• Input Impedance: RCA 100kΩ  |  XLR 200KΩ
• Bandwidth: >500kHz
• THD: <0.002% typical (20Hz–20KHz, 1W/8Ω)
• Damping Factor: >240 at 8Ω (20Hz–1KHz)
• Crosstalk: >90dB at 1kHz
• Weight: 57.2 lbs / 25.9 kg
• Dimensions: 16 in L × 17.5 in W × 8 in H (406.4 × 444.5 × 203.2 mm) With feet & binding posts: 16.75 in L × 17.5 in W × 8.75 in H
• Input Power Auto Voltage: 120VAC or 230VAC, 50 or 60 Hz
• Power Consumption Standby (Ready): <2W  |  Idle: 190W  |  50W/4Ω: 390W