more lateral fets

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ed
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more lateral fets

Post by ed » Sat Jun 09, 2018 3:35 pm

Oh the drilling, cutting, filing and bleeding...oh waily..
latfet pp.jpg
<waffle-mode)
This is a bit of a bitsa. It started life on paper as a simple platform to try and see what the sound of lateral fets was, if it could indeed be nailed down. The copious reports on the internet about how these lateral fets were the absolute best for audio caused my curiosity to lead me up the garden path yet again. Curiosity, oh waily waily. Originally a common drain complimentary pair of jfets into a common source pair of lateral fets...a la profet amp which I believe was the underlying base for F5. Well, it evolved, and the jfets were replaced by an opamp for simplicity. Matched pairs of jfets for the input are getting tricky to source, so I’ve left that for later.

I’ve decoupled the power supply to the extent that it now has two individual supplies for the input stage and the output...both way over specced as I intend to use this supply for other experiments...I still want to fiddle with the profet type front end and also a jfet ltp input stage. In a slightly different guise this whole amp could be the first 2 stages of a hockey puck amp.

Now for the irony.....

While researching SS in general I looked at various circuits and methods and came across the circuit for my aura 40 which I’d been using in the studio set-up for 20 years. Damn me, it was one of the original amps to use the new(at the time) lateral fets. I’d been listening to that sound for 20 years without a clue.

In true self-effacing style I took it to Steve’s last get together for a reality check...and yes, it is accountable.
</waffle-mode>

latfet ps.jpg
latfet baseback.jpg
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ed
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Re: more lateral fets

Post by ed » Mon Jun 18, 2018 2:07 pm

finished..just need to plug it in....pressure, what pressure...
latfet pp inside.jpg
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Cressy Snr
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Re: more lateral fets

Post by Cressy Snr » Mon Jun 18, 2018 2:10 pm

Remember to hide under the table Ed. :D
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Ant
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Re: more lateral fets

Post by Ant » Mon Jun 18, 2018 2:20 pm

Use a broom handle to hit the switch

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Mike H
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Re: more lateral fets

Post by Mike H » Mon Jun 18, 2018 6:43 pm

Not a peep since .. :lol:
 
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Re: more lateral fets

Post by ed » Wed Jun 20, 2018 5:03 pm

timid toad here......swidt

well the front end failed without so much as a puff of magic smoke....now adjusted the 16v balanced supply to 14v, a bit kinder to the opamps...but the back end tests ok, although it's only biased AB at the moment, hence timid toad....

it ran for about 45 mins and the sinks stayed at room temperature....I have plans for this case..mwahahamwahhaha
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