The Stax SRM-1 is a FET-input, pure class-A, DC-coupled amplifier designed specifically for electrostatic headphones, particularly the Stax Lambda series. It features separate sockets for both professional (pro) and normal bias headphones, providing versatility in use. Some models include a voltage switch at the back to accommodate different power requirements. Users often modify these units to improve performance, such as rewiring them for balanced operations. The amplifier is noted for its uncolored sound profile, delivering clean and clear audio with well-defined bass, mids, and treble across the frequency spectrum. It's capable of driving high-impedance headphones, including the Stax Omega series, without clipping, making it a powerful choice for serious audio enthusiasts. The build quality is solid, with discrete components that make the unit user-serviceable, although some users recommend replacing the electrolytic capacitors in the power section due to aging. Additionally, users have found it sensitive to grounding issues and advised to connect it properly to avoid interference. Overall, a refurbished SRM-1 can yield exceptional sound quality and detailed audio reproduction, making it a valuable asset for headphone audiophiles.
