PST-100 MKII

About the PST-100 MKII

The Ypsilon Electronics PST-100 MK2 is a high-end line preamplifier that combines an in-house transformer attenuator with a tube-based active gain stage. In active mode, it uses a no-feedback single-ended C3m triode stage transformer-coupled for gain, while passive mode allows signal attenuation without the active stage. The design emphasizes minimal signal path, point-to-point wiring, custom pure silver wire, and valve rectification with choke filtering in the power supply. Manufacturer and review sources describe it as a flagship preamp for highly transparent, low-noise systems. The standard PST-100 Mk.II is listed at $37,000 by Stereophile, while sources also mention a passive-only PST-100 TA variant at a lower price.