SRM-500T Vacuum Tube Headphone Amplifier

The Stax SRM-500T Vacuum Tube Headphone Amplifier is a pivotal “energizer” in Stax’s esteemed lineup, designed to unleash the full potential of their electrostatic earspeakers. Succeeding the long-standing SRM-006tS, this hybrid amplifier combines a FET input stage for pristine signal integrity with a vacuum tube output stage, featuring a pair of 6FQ7/6CG7 tubes, to deliver a uniquely warm, transparent, and natural sonic signature. A key innovation is its newly designed power transformer, which significantly boosts power efficiency and refines sound quality. The SRM-500T is housed in a robust, non-magnetic aluminum chassis, meticulously engineered to suppress vibrations and external noise. It provides both RCA and XLR (balanced) inputs and the essential 580V DC Pro bias output for Stax headphones, alongside a convenient RCA parallel output. With its wide frequency response (DC-90kHz) and extremely low distortion, the SRM-500T offers a smooth yet highly detailed presentation, enriching vocals and adding body to the low-mid range. This amplifier serves as an excellent gateway to the world of high-end electrostatic sound, particularly complementing Stax’s Lambda series earspeakers.