DIY Sony VFET lottery discussion

Jason or other moderators: I'm super excited to have been able to get one of these amps in the lottery! In order to maintain some sort of cosmic balance, I'd like to donate a pair or two of Vfets to the diyAudio site to accompany some of the future kits that will be offered. I purchased them in 2015 from acroman.

How can I follow up with this?

May I clarify what you got. 2 Sony 2SJ28 or 2 IOR IRF250 ?
On each side of 6L6’s pics there is one Sony 2SJ28 and one IRF250.
Thank you.
 
Something worth mentioning - Nelson really put in the hard yards on the output stages, semi-assembling and testing the most tricky parts on all 360 of them including the VFETs to ensure everyone building the amp had the best possible chance to not ruin their project. This was to ensure that anyone building the amp, even "advanced beginners", had a good chance of a successful build.

That got me thinking two things:

(1) Nelson is crazy, but in a great way! Thanks for doing this!!

(2) Since these amps / kits are designed for "advanced beginners" like those who successfully built an ACA or other simple kit, I think it would be nice to have more of these VFETs in the hands of such builders. With the first round of the lottery, a lot of weight was given to the long-term members who contribute(d) a lot to the forum. This is a great way to say "Thank You" to those members, but it also means that the "advanced beginners", who tend to be newcomers with less contributions to the forums, are left behind. That's just how I see it, but maybe it would be worth to consider this for the coming lottery rounds.
 
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Fully agree. The problem with the CSX1 is that it was present in basic document form, while the CSX2 was presented with fully made PCB (still available today at DIYAudiostore.com) and component kit and even the chassis supplies with angle mounting brackets were easily available for purchase. Even more convincing 6L6's online build tutorial. The CSX1 didn't stand a chance.

...

I think you may be confusing the CSX2 with the 2017 diy Sony VFET amp?

I've been eyeing the CSX1/2 for a long time. Some day I'll find the time, and transformers, and the brackets...
 
FWIW, I was one of the fortunate few who "won" the lottery even though I had been a lurker for years and only registered the day before the lottery... a bit of a statistical fluke that sorta validates the random nature of the lottery draw in a way, I guess.

Anyway, though I do have some electronics experience from my school days, I have never tried one of these DiY kits before, and I'm super excited to share whatever my totally noobie experience will be... so far, the ordering process that I just completed this morning went super smoothly... thanks to everyone for making this whole project possible and this process fun and exciting.
 
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6L6

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Matthias -

I realize I did not articulate that properly...
The lottery will reward the heavy posters, (and has) but as those winners are removed from the pool the newer people (who are the advanced beginners in large part) will have a greater possibility of winning.
 
Yes... but my point was: isn't this the opposite of what was intended?

Since the target is "advanced beginners", I'd say the next lottery should be considered to be more in favor of these guys.


It's my understanding that the advanced beginner designation refers to the difficulty level of the build (which is good information to have for any kind of kit).

So it is informational, to let the builder know how much experience one should have to tackle the project comfortable, if I understand it correctly.
 
May I clarify what you got. 2 Sony 2SJ28 or 2 IOR IRF250 ?
On each side of 6L6’s pics there is one Sony 2SJ28 and one IRF250.
Thank you.

I have some extra 2SJ28 (P-ch) vFets in TO-3 cans, each marked KF-33 that came from Acronman in Singapore. I am willing to get these into the hands of someone that wants to pick up one of the "vFet-less board kits" that will be offered after the lottery is concluded. This will enable someone else to build one of these great amps. I do not have any IOR IRF250...
 
I have some extra 2SJ28 (P-ch) vFets in TO-3 cans, each marked KF-33 that came from Acronman in Singapore. I am willing to get these into the hands of someone that wants to pick up one of the "vFet-less board kits" that will be offered after the lottery is concluded. This will enable someone else to build one of these great amps. I do not have any IOR IRF250...

Pm sent.
 
I think you may be confusing the CSX2 with the 2017 diy Sony VFET amp?

I've been eyeing the CSX1/2 for a long time. Some day I'll find the time, and transformers, and the brackets...

Going by Mr Pass's timeline release of the VFets here:

https://www.diyaudio.com/forums/att...34-diy-sony-vfet-pt-1-a-diy-sony-vfet-pt1-pdf

The CSX1 is version 1 2013 Sony VFETs Part 1

The CSX2 is version 2 2014 Sony VFETs Part 2

Don' t know about the 2017 DIY VFet release? But both versions are very different and from what I read (vaguely) both have different (but still good) sound. It will be interesting to see how the new single ended designs will sound :spin:
 
I have some extra 2SJ28 (P-ch) vFets in TO-3 cans, each marked KF-33 that came from Acronman in Singapore. I am willing to get these into the hands of someone that wants to pick up one of the "vFet-less board kits" that will be offered after the lottery is concluded. This will enable someone else to build one of these great amps. I do not have any IOR IRF250...

I need 1- 2sj28 if you can spare it?
 
Going by Mr Pass's timeline release of the VFets here:

https://www.diyaudio.com/forums/att...34-diy-sony-vfet-pt-1-a-diy-sony-vfet-pt1-pdf

The CSX1 is version 1 2013 Sony VFETs Part 1

The CSX2 is version 2 2014 Sony VFETs Part 2

Don' t know about the 2017 DIY VFet release? But both versions are very different and from what I read (vaguely) both have different (but still good) sound. It will be interesting to see how the new single ended designs will sound :spin:

I’m pretty sure the Part 1 article describes both CSX1 and CSX2 designs which are Common Source Mode. His Part 2 article shares his design for a Common Drain Mode. They never really named this version and I think most people refer to it as Part 2 VFET or 2017 VFET (the boards that are being sold on the diystore are for this version).
 
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It's my understanding that the advanced beginner designation refers to the difficulty level of the build (which is good information to have for any kind of kit).

So it is informational, to let the builder know how much experience one should have to tackle the project comfortable, if I understand it correctly.

Correct. I wanted to publish a note about the difficulty level so everyone, especially newbies, were aware of the difficulty level of this project. Hence the "Is this for me?" section of the store's VFET information page.

We describe the ACA as a beginner project, but still some people gave us feedback that they were beginners but they struggled. It's arguably "beginner" for someone who has done some soldering before and "advanced" for someone who doesn't know what a soldering iron is. Everything is relative.

I have been thinking about how to better represent difficulty level, and I think an accompanying list of abilities, knowledge and experience that is expected is a better idea than "beginner", "intermediate", "advanced". By the way the software we use at guides.diyaudio.com has no way to customize the terms, so it is stuck with "easy", "medium", "hard" which are even more subjective. Easy for... who?

Anyway... based on feedback I received "advanced-beginner to intermediate" was agreed upon as something acceptable to publish. "advanced-beginner" is not intended to be the target market, just the absolute bottom entry point in terms of experience and I wanted to make the point that this is "not recommended for first time builders".

As ever, we'll learn from feedback and iteratively improve communication...

FWIW, I was one of the fortunate few who "won" the lottery even though I had been a lurker for years and only registered the day before the lottery... a bit of a statistical fluke that sorta validates the random nature of the lottery draw in a way, I guess.

Welcome aboard!

I realize I did not articulate that properly...
The lottery will reward the heavy posters, (and has) but as those winners are removed from the pool the newer people (who are the advanced beginners in large part) will have a greater possibility of winning.

As Jim said, the lottery heavily favoured established contributors, while also letting people like buckaroo have a chance (there were 850 lurkers I think, and 5 got one). There was no way of doing things that would make everyone happy. Now the heavy hitters are mostly out of the pool, there are half as many tickets, and odds for everyone appear to be approximately doubled for round 2.

Whether the spread was a good one will only be evident once we see who (successfully) builds it and shares the experience with the community in a reasonable time.
 
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I am probably one of those "lurkers" although I prefer to think of myself as dormant or having limited multitasking skills. I am sorry to report to those at the top of the waitlist that i paid for my kit today. I was egged on by the infamous post #308, if someone whiles about a lottery, well then i might as well build this one. Had better odds with this than with SNKRS or Comic-con tix.........
 
Everyone who didn't get one, remember that this is far from the last interesting project.

I have a list...

:snail:


Kudos, and thanks for putting in the efforts! I'm keeping hope for round 2, or the next incarnation! After successfully building 2 ACA's and having a blast during the build and listening since, I can't wait for the opportunity to engage on the next project. Congrats to all the winners thus far!
 
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