PA400

S.M.S.L PA400 Flagship GaN 500W Stereo Power Amplifier

The S.M.S.L PA400 is a reference-class Class D stereo power amplifier that redefines desktop and home audio amplification. By combining cutting-edge Infineon Gallium Nitride (GaN) FETs, an ultra-high 1MHz switching frequency, and a high-end Texas Instruments PGA2311 analog volume control, it delivers a colossal 500W of total output power with the organic warmth, immense liquid texture, and detailed resolve of a reference Class A amplifier.

Next-Generation Infineon GaN FET Technology

At the heart of the PA400's output stage are cutting-edge Gallium Nitride (GaN) Field-Effect Transistors from Infineon. Unlike traditional silicon transistors, GaN FETs switch at exceptionally high speeds with near-zero dead-time distortion and extremely low on-resistance. This technological leap results in unprecedented power efficiency, lightning-fast transient response, and a highly realistic, effortless delivery of complex musical dynamics.

Ultra-High 1MHz Switching Frequency for Pure Analog Sound

While standard Class D amplifiers typically operate at switching frequencies between 300kHz and 400kHz, the PA400 drives its switching frequency up to a staggering 1MHz. This ultra-high frequency pushes high-frequency switching noise far beyond the audible spectrum, allowing S.M.S.L to implement a gentler, more phase-linear low-pass output filter. This breakthrough completely eliminates 'Class D glare', yielding a remarkably smooth, sweet, and analog-like high-frequency presentation.

Texas Instruments PGA2311 Analog Volume Control

To preserve the absolute purity of the incoming audio signal, the PA400 utilizes the high-end Texas Instruments PGA2311 stereo volume control chip. The PGA2311 utilizes a digitally controlled, precision resistor-ladder network that adjusts volume strictly in the analog domain. This ensures near-zero channel deviation, maintains a perfect stereo image even at whisper-quiet levels, and keeps the system noise floor practically nonexistent.

Fully Balanced XLR Architecture & Power Boost

Designed from the ground up as a true balanced system, the PA400 features premium XLR balanced inputs that completely isolate ground-loop noise and electromagnetic interference. The fully balanced signal path ensures exceptional channel separation and maximum dynamic range, driving an unblemished, high-current signal directly to your speakers to render a deeper, wider, and more holographic three-dimensional soundstage.

Premium CNC-Machined Chassis & Audiophile Build

Every element of the PA400 is optimized for pure high-fidelity performance. The amplifier is housed in S.M.S.L's premium, solid CNC-machined aluminum alloy chassis, which provides exceptional shielding against external interference and mechanical resonance. Internally, a heavy-duty power supply with active PFC ensures stable current delivery even under demanding dynamic loads, complemented by gold-plated inputs and high-current speaker binding posts.

Specifications