Ever try a JFET power amp?

I was aware of the technology, but have not investigated it. A quick scan of the datasheet tells me that these are intended for power conversion applications where they are used as switches. They can be operated in linear mode and the gain (transconductance) is HUGE. Orders of magnitude higher than a vacuum tube or the typical small-signal JFET. The capacitance is quite high as well, which means a linear power amp circuit will need to have much lower impedances than a tube amp to achieve the same freq response. Intriguing.

This is the pricing at Mouser.
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Seems like it'd be something interesting to play with - especially since you could get quite a lot of power in a single-ended Class A output stage. Feeding it a low impedance is easy enough. The heatsink? Maybe not so easy - or light.
 
I suspect something like this would be easy to adapt, you wouldn't need to parallel the JFETs in the power section of course. Although I wonder, how tube like are power JFETs, a class AB MOSFET section should sound as tube like as JFETs I would think?

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MOSFETs & JFETs have the same transfer function.

Where did that schematic come from?

I'm not seeing the advantage of a power JFET over a power MOSFET in this application.
 
Chuck D. Bones said:
MOSFETs & JFETs have the same transfer function.

Where did that schematic come from?

I'm not seeing the advantage of a power JFET over a power MOSFET in this application.
Click to expand...

Apologies, here's the link, it's one of those Russian circuits, I think the LTP circuit, with an AB Mosfet Power amp if you want real volume, as is this creates a nice little power amp sim that produces ~250mW, you can even load it with an inductive load if you want the speaker impedance response.

 
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