Sony VFET Amplifier Part 2

Perhaps something like this for the VFET FE? It's a start at least...
 

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...just two small questions luvdunhill,



1- Different values for source resistors on output is your effort for tighter matching ?

2 - How long is main board ?....i am halfway to building a chassis and was counting on two pairs a side so now i am hopping this still fits.



Carlos


I am allowing for source resistors, they aren't present on the official VFET2 schematic. They will need to be jumpered with a bit of wire if not used. The article says they aren't needed and the lack causes some nice benefits, but with the extra device (3 deep) it seemed wise. I am open to removing them, but definitely wanted a prototype board to have the option.

All my posts should have dimensions on them - the width is on this very page.
 
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Finally getting this project off the ground. Thanks to Botte and Flocchini for their help in building this project, and La Ode for the board layout.

Here is a video link to the working prototype.
Some production boards will need to be respun to add a wire to the output board and to eliminate the TO-220 bipolar in the front end, also to use wider spacing for TO-92 TL431.

https://youtu.be/kWSlbYg01pQ

Also viewable/listenable on instagram @emojiviasound
 
Here's the VFET2 Front End. I'm trying a different board house for this than the output stage (PCB Way versus Elecrow). Just put the order in for the front-end and the output stage already shipped from PCB Way.
 

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Congrats Tea-Bag.

Was there a heatsink attached to the bracket? (Maybe I missed it.)
How large/thick is that bracket you used?

Cheers,
Dennis

HI Dennis, Not attached yet to a larger heatsink. Its thick enough to run at a low bias for 30 minutes or so.

I believe Botte set me up with getting this bracket from the US. (I cant seem to find resource) It is a very thick bracket, that the PINS barely make it to the PCB. Something a little thinner I think would work well once attached to the heatsink. I will set up a seperate thread for the board soon.
I would not take this on without a half-decent drill press. A cordless one, unless your gifted is not going to make anything line up right. All the holes are drilled with plenty of space around them, and then covered a little teflon sleeve covers the pins where possible.
I would not call this a novice project at all, unfortunately.
 
The one and only
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Attached is the bracket I had made, and which I am using to revise the board.
It has been provided to DIYAudio for the purpose of the kit, and they are in
charge of having them made.

I expect to have working units in the Store chassis around the end of Feb.

:cool:
 

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Attached is the bracket I had made, and which I am using to revise the board.
It has been provided to DIYAudio for the purpose of the kit, and they are in
charge of having them made.

I expect to have working units in the Store chassis around the end of Feb.

:cool:

Thanks Mr Pass for last kit update informations.
Great i have complete all front end components and vfets so
i stay in tune for other news about final simplified one pair mono Vfet2 amplifier version.
Could DiyAudio Store sell official pcb's only ?
This option give more chances afford some as well for diyers without vfets on bench.
Kind regards :happy1: