Ypsilon Electronics PST 100 MKII

Greetings,

For sale is my Ypsilon PST 100 MKII in silver finish. Serial number 024. This preamp was purchased preowned in 2024, but was built in 2011. I have used this preamp sparingly so there is plenty of tube life with their 10,000 hours estimated lifespan.

Sonically this preamp is invisible, but still sounds organic and natural with great PRAT and dynamics. It is an open window to the music.

Check out the positive Michael Fremer review and John Atkinson’s measurements from Stereophile magazine!

Cosmetically there is a ding in the front faceplate, and another at the top right corner. Some scratches on the top cover as well. Input RCA 3 is missing the prong holders but still functions. This is why I have rated the unit as 7/10, but again sonically it is perfect. A very affordable way to get that Ypsilon sound in your system!

Original box and flight case included along with the substantial metal remote.

Buyer responsible for PayPal, shipping and insurance costs. 

Please message me with any questions, thank for looking!

PST – 100 is most certainly an impressive addition to YPSILON’s 100 series. It approaches the concept of pre amplification in an outstanding way. Its heart lies in the in house made transformers used for attenuation. In addition its valve state circuit combined with exquisite materials produce the finest and most elegant sound that any pre amp could ever achieve. 

Conventional wisdom suggests that the most critical part of a preamplifier is the active circuit design. We, however, believe that the means of signal attenuation (the volume control) is the most critical to the overall sound of a preamplifier. Most designers use resistor attenuators for volume control. We have used resistor attenuators with high quality resistors (Vishay, in the past, felt unsatisfied from the character they induced in the signal. We developed a very special transformer as the means of attenuation, using special winding techniques and highest quality wires and cores. Its performance suppassed that of the best resistor attenuators. In a transformer the magnetic circuit can be ultra linear when the very best core materials are used. The sound of such materials is much more musical and detailed compared with the best resistors. A transformer attenuator with 31 taps is used in the PST100 mk2 providing a total attenuation of 54db in its lowest tap. 

The active gain stage is a no – feedback s.e. ,C3m triode, transformer coupled. The power supply uses valve rectification(using the 6CA4) and choke filter. Wiring is point to point with custom made pure silver wire. The transformer attenuator is placed after the valve stage, preserving the purity and micro details of the signal. The gain is 16db. Output impedance is 150 Ω max. PST 100 mk2 is the pinnacle in preamplification. It is a must have component for building a “no holds” system. 

PST 100 TA PST 100 is also available without the valve stage for systems that don’t require additional gain. This version is equipped with the transformer attenuators and is called PST 100 TA. Notice that it is fully upgradeable to the full version at any time by returning to factory.

SPECIFICATIONS PST-100 MKII