2. amps-preamps
  3. 1411998229

Pass Labs Vfet amps

I heard the priceless Pass Labs Vfet Amps in the Sony suite at the NY Audio Show this weekend. Sounded wonderful!! There were only six Amps made worldwide of which Sony owns 4 and Pass kept 2. Nelson Pass purchased the remaining world wide supply of Sony Vfets and used them to build the 40th anniversary Sony reference Vfet amplifiers. Anyone else hear them or understand why they're so special?? Sony flagship speakers sound good but still can't wrap my head around Sony as a "high end" audiophile quality product... Would have loved to hear Vfets on Wilson XLFs, Focal Grand Utopia or YG Acoustic speakers but that will never happen unfortunately. If Pass XS series Amps cost $85k a pair what would it take to get Sony to part with a pair of their Vfet mono blocks?? If only I had an extra $million dollars to play with... Probably worth it!
lepps200228
jafant
18,798 posts
 
Agreed-

I would like to hear from owners of the ES speakers who use Pass Labs gear to drive them. This combo has been around for some time now. Odd pairing or not, we can never underestimate the power of synergy. Keep me posted and happy listening!
schubert
7,386 posts
 
The Sony Vfets amps were the best I ever heard.
bombaywalla's avatar
bombaywalla
1,958 posts
 
Anyone else hear them or understand why they're so special??
VFETs are also called Static Induction Transistors (SIT) & their I-V characteristics resemble that of a triode. VFETs/SITs basically behave like a voltage-controlled variable resistor (rather than a voltage controlled current source as MOSFETs & JFETs do). You already know that the triode vacuum tube is perhaps the most linear power amplification device. So, here we have a semiconductor with triode characteristics & the semiconductor, in comparison, has way more life than a vacuum tube. So, best of both worlds.
nice paper by Nelson Pass on his 1st Watt website:
http://www.firstwatt.com/pdf/art_sit_intro.pdf
theduke
372 posts
 
Why doesn't some semicondustor company resume production of these devices? If they were available I could see numerous hi-fi companies using them in their equipment.
omsed
145 posts
 
They are very expensive in the quantity high end mfgrs would use them, and there are not many around to experiment and build protos with. Most mfgrs are not that innovative and stick with pretty common devices and circuits, no matter what technobabble they babble about.
More to discover