Sony vFET Amplifier Part 2

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#1,864
proton74 said:
I have received this VFET with the my 2 KIT :
2SJ28 : 89 / 84 or 89 (it's dificult to read) 2SK82 : 81 / 81

2SJ28 : 118 / 118 2SK82 : 86 / 86

Can you tell me if I could try to make the amp with the original 2015 VFET PART2 with to pair of VFET per channel ?
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It should be 89, as they were adjacent pieces in the sort and would not
generally be off by more than 1

😎
 
#1,867
Recieved my kit a few weeks ago and I am really looking forward to build my amp. Been following this project since the very start and I do appreciate very much all the work and efforts that has been done here.

I´ve started collecting parts and the first resistors arrived today, my iron heating up already. I found that R33 and the LED are double up on the board. There are two of both. No big deal but take into consideration when collecting parts.

Andreas
 
#1,868
andRookie said:
Recieved my kit a few weeks ago and I am really looking forward to build my amp. Been following this project since the very start and I do appreciate very much all the work and efforts that has been done here.

I´ve started collecting parts and the first resistors arrived today, my iron heating up already. I found that R33 and the LED are double up on the board. There are two of both. No big deal but take into consideration when collecting parts.

Andreas
Click to expand...

Since the boards are the same for the L and R channels the led on both sides of the board allows you to wire a led from each board to the front panel without long wires running inside your case.
 
#1,870
I did some A/B'ing of this amp with some of my other amps last night. The V-fet has the mids of the M2 but is much more dynamic and quicker than the M2. I have always thought the Mids of the M2 were the most tube like of the Firstwatt amps I have heard. Keep in mind I have big horns. I am using the BA'3 front end for a preamp. The F6 is almost as dynamic and quick but has a more SS sound in the mids. The soundstage of the V-fet is better than either one. Anyone that has tried to compare amps against each other know it is hard to adjust the volume to be equal unless you use equipment which I did not. A slight volume increase of one amp over another can change your perspective.

I have a number of different tube amps I also compared it to. One of them is a Jack Elliano designed 45 tube amp which has some of the most clear and clean vocals I have ever heard from an amp. The V-fet is about dead even with vocals in my comparison with just a touch of pleasant coloring. The soundstage is a little better with the V-fet IMHO. The V-fet has a very SET like soundstage only bettered by one amp I own a SE 300B which is not a fair comparison, the V-fet being a push pull and the 300B I own being a single ended. The V-fet is not supposed to sound like a SET. Nelson's FW SIT fills that role. I like the think the V-fet has more of the push pull 300B amp sound but then I have never heard a push pull 300B. I am not a reviewer so read all this with reservations of who is saying it. This is just my quick limited one song comparison of the V-fet with some of the dozen or so amps I now own and have built.

I am still being amazed with the sound of this amp. It has exceeded my expectations. I hope this post lights a fire under the rest who own this kit and hurry up and build. I look forward to hearing their opinions.
 
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#1,875
mr_whocares said:
we are very looking forward to see your review and the comparison between the original vfet p2 and the diy version ;-) .
best wishes
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Thanks for your care but unfortunately I do not build diy version, I just want to buy vfets but I can not remove PCB so I must buy full kits.
I think the sound of two pair version and one pair version are close, just want to tell you that I like the sound without global feedback in two pair version and the one pair version fixed global feedback😡
 
#1,876
nagini262 said:
... just want to tell you that I like the sound without global feedback in two pair version and the one pair version fixed global feedback😡
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oh... very interesting finding.

eliminating the global feedback in the single pair version should not be a very big deal (?), however I was expecting a more detailed and controlled sound with the global feedback 🙂

would you please describe a bit the sound differences between the two options?

have you made any modifications to the amp or you have implemented the original design of Nelson?

Thanks and regards
 
#1,877
mr_whocares said:
oh... very interesting finding.

eliminating the global feedback in the single pair version should not be a very big deal (?), however I was expecting a more detailed and controlled sound with the global feedback 🙂

would you please describe a bit the sound differences between the two options?

have you made any modifications to the amp or you have implemented the original design of Nelson?

Thanks and regards
Click to expand...
Single pair version without local feedback but fixed global feedback, two pair version fixed local feedback and optional global feedback so I guess the sound of both are very close.
In the two pair version, the sound with global feedback is close to face of loudspeaker and you will heard the sound direct from your loudspeakers, the sound space is small. When you switch to without global feedback, you will heard the sound around of you, the sound come to your ear from anywhere in your room, it's very close surround sound so you can heard the large sound space. You must sit at your position and someone help you to switch the option, it's hard to find the difference if you come to your amp to take the switch and heard.
I built with the good parts without modify.
 
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#1,878
Nearly there.

Finished the chassis and power supply. Just waiting on a custom trafo.

Boards are stuffed and pass all the ohm test points.

BK
 

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