STAX SRM-500T

Hybrid electrostatic amplifier with tube output stage

The STAX SRM-500T is a high-quality hybrid driver amplifier for electrostatic STAX Earspeakers. As the successor to the SRM-006tS, it combines the precision of a FET input stage with the musical smoothness of a classic tube output stage.

The input stage uses a STAX custom low-noise Dual FET, while the output stage is built around 6FQ7/6CG7 twin triodes. This combination delivers a clear, fast, and finely resolved presentation, enriched by natural warmth, spacious imaging, and a pleasing sense of body through the midrange.

The SRM-500T continues STAX’s proven tube driver circuit concept, but adds a newly designed power transformer and more efficient power supply architecture. This results in more stable performance, lower power consumption, and a more controlled sonic presentation compared with earlier STAX tube driver units.

The mechanical construction has also been upgraded. Its more rigid chassis, using non-magnetic aluminum, helps reduce vibration and external physical noise. The fully DC-coupled amplifier circuit avoids coupling capacitors in the signal path, preserving transparency, speed, and immediacy.

With RCA and XLR inputs, RCA Parallel Out, and two STAX PRO Bias outputs, the SRM-500T integrates easily into high-quality headphone systems. It is an excellent choice for listeners who want the unmistakable STAX sound with added warmth, body, and spatial richness.

Technical Specifications