Sony vFET Amplifier Part 2

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#821
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#824
audioexplorations said:
Is it possible to build the VFET part 2 amp with a single pair of 2SJ28/2SK82 per channel? What would be the consequence and how much would the watts per channel reduce down to? Thanks
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I have a single pair version running and the distortion is a little bit higher, other than that, it works fine and still sounds great! As for the power we will have to wait for Nelson on that.

I think the kit from the DIY store is going to be single pair.
 
#826
Any reason on the CSX2 we couldn't just use the bits in the VFET2 schematic around the IRF MOSFETs? I have overlayed the parts in the attachment from both designs and it's very possible to make a board that will do both circuits.

So, my questions are:

1.) Is there any reason to put the parts in the box marked "CSX2" on my PCB? It seems the parts in the left-most box marked "VFET2" will work in both cases. Is that correct?

2.) Will it hurt the CSX2 circuit to have the bits in the right most "VFET2" box? The Z2 and Z6 seem like they are benign / protection duty and same with R18 and C8. I suppose they could just be left unpopulated in "CSX2" case, but I'm wondering if they will help / hurt / do nothing 🙂 For example, C5 is just a bypass which is in the "CSX2". It will probably help the "VFET2" circuit, but definitely won't "hurt" or "do nothing". I'm interested in similar answers for the bits in the right-most "VFET" box.
 

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#828
luvdunhill said:
Any reason on the CSX2 we couldn't just use the bits in the VFET2 schematic around the IRF MOSFETs? I have overlayed the parts in the attachment from both designs and it's very possible to make a board that will do both circuits.

So, my questions are:

1.) Is there any reason to put the parts in the box marked "CSX2" on my PCB? It seems the parts in the left-most box marked "VFET2" will work in both cases. Is that correct?

2.) Will it hurt the CSX2 circuit to have the bits in the right most "VFET2" box? The Z2 and Z6 seem like they are benign / protection duty and same with R18 and C8. I suppose they could just be left unpopulated in "CSX2" case, but I'm wondering if they will help / hurt / do nothing 🙂 For example, C5 is just a bypass which is in the "CSX2". It will probably help the "VFET2" circuit, but definitely won't "hurt" or "do nothing". I'm interested in similar answers for the bits in the right-most "VFET" box.
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Many questions.. My opinion is that you should build it as Nelson says. There are many reasons he made the choices he did.

He did say you could leave off the Zeners at your own risk. As for R18 and C8 and their mirror. They help with turn on surge and allow more peak voltage on transients and should be in the circut.

My two cents.
 
#834
though , just circulating hot air in enclosure isn't most efficient (read -silent) way of removing heat

not to mention increase of temperature of all components in case

what you need is separate inlet or outlet for that tunnel heatsink

you can use plastic foil as tunnel extension
 
#835
Zen Mod said:
though , just circulating hot air in enclosure isn't most efficient (read -silent) way of removing heat

not to mention increase of temperature of all components in case

what you need is separate inlet or outlet for that tunnel heatsink

you can use plastic foil as tunnel extension
Click to expand...

Thanks! That's a good idea, I will drill some hole at back panel, the air flow will through out....
I was diy: Aleph 3, Aleph 2, Aleph 1.2, Aleph X (not success), FW F2, FW F4, FW F5 (standard, turbo V2, turbo V3), FW F6, Amp Camp Amp #1 (ACA), Delite Amp, The Amazing FET Circlotron, Power Follower 99, Amplifier End, Sewa, Naim NAP140,... and now is Sony VFET part 2. I think the VFET part 2 and the Amplifier End are the best especial amplifiers.
 
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