Better performance would certainly be different.
My guilty pleasure amplifiers are the Beast With 1,000 JFETs.
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yup , my fave can amp
easily reconstructed to serve as MC Pre-Pre
Depends on what you think of as linear. You can get pretty decent distortion
numbers with a single-ended Jfet, and if you want better you can operate
balanced and/or use feedback.
Careful selection and matching is a big help...
I routinely see SE J113's getting down to .001% under line level conditions, and
I have examples of 1 watt SE amplifiers at .01%. Since it is primarily 2nd
harmonic, it can be largely cancelled with balanced operation.
The P channel version of the J113 would probably be the J176, although it does
not have the nicely complementary properties of the 2SK170/2SJ74.
numbers with a single-ended Jfet, and if you want better you can operate
balanced and/or use feedback.
Careful selection and matching is a big help...
I routinely see SE J113's getting down to .001% under line level conditions, and
I have examples of 1 watt SE amplifiers at .01%. Since it is primarily 2nd
harmonic, it can be largely cancelled with balanced operation.
The P channel version of the J113 would probably be the J176, although it does
not have the nicely complementary properties of the 2SK170/2SJ74.
What I was thinking of linear was that a change in Vgs will always give same change in Id regardless if the change is from -1V to -1.5V or from -4V to -4.5V.....so there was a linear relation instead of a "square law" relation. But it may be a wrong way of thinking? ….but if you only use a very small part of the curve it may be linear "enough"? …..I am just trying to understand the curves……and got confused by the "square law" relation between Vgs and Id 
Is there an appropriate JFET in a surface mount config? this could be replicated as a production item! Or have a small batch of populated boards made. So that’s easy probably, but then there’s buying 1000ish JFETS so The SE j113 would prob be necessary, which might quash the whole deal
Also Of course loses a bit of the outrageous factor, and knowing Nelson the JFETS are probably matched!
Also Of course loses a bit of the outrageous factor, and knowing Nelson the JFETS are probably matched!
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Now this sounds interesting. Digikey/Mouser sell 1000 pcs of J113 for around $100.
And 2000 pcs $170. with no heat sinks needed. I'm in.
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Too compact would require a fan, but smaller pcbs would be much cheaper.
And smt packages could be on both sides of the pcb, if the heat allows.
There are also cheaper standard 10k J113 OEM packages that can be shared.
Don't forget you will need a big drive voltage, due to the follower topology.
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Only if you are a glutton for punishment
That's what summer interns are for. I think a PCB might be laid out that could support the power dissipation, but it would not save any space vs the TO-92 devices. Each SOT-23 would need some surface area for its drain connection.
The very short "legs" SMD has should give less inductance and maybe capacitance? ….if we have 1000.....it could mean something?
Soldering 2 x 1000 SMDs…..I would give it some days/weeks….e.g. solder 10 every day from Monday - Friday and 20 Saturday and Sunday. It could be a good mental exercise every evening preparing for a good nights sleep…….
Soldering 2 x 1000 SMDs…..I would give it some days/weeks….e.g. solder 10 every day from Monday - Friday and 20 Saturday and Sunday. It could be a good mental exercise every evening preparing for a good nights sleep…….
Input capacitance would be tens of nF, so this will need a low impedance source.