JFET instead of MOSFET?

Frequently asked question on transistors: types, substitutions, how to test, use and misuse them.
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shicky
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Post by shicky »

This might be a noob question.
I am unfamiliar with JFET and its operation. But small signal model looks very similar.
Is there any reason why stompbox designers are using JFET instead of readily available MOSFET?

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earthtonesaudio
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Post by earthtonesaudio »

JFETs are the most common depletion mode device, they're more robust to ESD than mosfets, and they have their own unique sound.
rocklander wrote:hairsplitting and semantics aren't exactly the same thing though.. we may need two contests for that.

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shicky
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Post by shicky »

Please correct me if im wrong.
I thought MOSFET is used more and JFETs are not used as often these days.
Is there any particular reason why stompbox designers are using depletion device?
Aren't depletion devices harder to work with?
Is there any MOSFET based pedal?

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earthtonesaudio
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Post by earthtonesaudio »

Hm... I don't think I actually answered your question. The reasons I gave are not necessarily representative of "stompbox designers" in general. I would guess the reason most stompbox builders use JFETs is because they were able to get a good-sounding distortion out of them without having to make too many changes to a schematic they found online. 8)
rocklander wrote:hairsplitting and semantics aren't exactly the same thing though.. we may need two contests for that.

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