Sony VFET Amplifier Part 2

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I did see that people were buying from acronman electronics. I looked up his website and they seem to be out of stock.
Keep a look out and hope I guess.

Acronman has no stock left and will never have new stock.
On the internet (Ebay, Aliexpress, Alibaba) only fakes can be found... (I know, bought from different sellers, all fakes or relabelled 2sk60) so no, there are no sources for our precious VFET's anymore.

Sometimes in the DIYAudio 'Swap Meet' they are offered by members who are not going to finish their VFET project.
 
The one and only
Joined 2001
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For clarity, matching is only needed to see to it that devices wired in
parallel share the current roughly equally.

With this push-pull design with single VFETs (no devices in parallel) you do not need to match devices across polarities (P-N) and you do not need to match devices across channels (N-N and P-P). So, no matching per se is required.

What you do need to know though is the VFETs' Vgs for Id=0.5A with Vds=19V to set the appropriate bias voltage. Otherwise your VFETs might burn up when you first switch on the amp. Here's how:

Here is an example test setup
 

As some of this might be taken for granted (and Thanks giving is not an anuall celebration in the Netherlands), I’d like to express my thanks and gratitude to Nelson Pass & the DIYAudio store team, for making this design & VFET’s available and to all of you for your support and enthusiasm for this project.


Yesterday, after a few days burn-in, I had a first proper listening session with the newly build Sony VFET amp. The amps is behaving well, staying at about 23C above ambient, low DC offset & is very quiet. I was blown away by the improvements over my old F5. These might be subjective superfluous, but to me the sound is much more spacious, with much better separation and there is so much more natural tonal richness their too. The whole listening experience left me feeling in awe, completely satisfied and relaxed. Hard to believe a “good” amp can make this much difference and that myself and so many others have been/are missing out on so much goodness.
 
VFET Amp vs. SIT-2

Has anyone lucky enough to access to both compared the Sony VFET DIY project amp to the First Watt SIT-2? Just curious if they're in the same flavor category - or apples and oranges.

Thanks!

I have both amplifiers and:
- I "absolutely love" the SIT-2
- I "love" the VFET amp

I also own 4 the original Sony VFET amps and have collected them since 1978, always loved them but the SIT-2 is entirely different. For lack of better expression, the VFET amp has an ultrasonic characteristic that is unlike any other amp I own or have listened to, the SIT-2 may be slightly less detailed but it is simply magical with my Altec Valencias!

Armin
 

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