Mesmerizer Transistors

[VanWhy]

I'm building the Mesmerizer PCB but I ordered 2N5458's instead of 2n5485's. They are both switching JFETs.

Are the 2N5458's suitable for this circuit? Or is it picky with those transistors? From the schematic it looks like they are not biasing so it might be ok? I have the 2N5457 for Q1 and Q2.

Been waiting for the transistors and just hoping they can be subbed.

 

[Feral Feline]

TYPE	Vgs off	V	Idss	mA	gfs	mS
	min	max	min	max	min	type	max	@
2N5458	-1.0	-7.0	2	9	1.5		5.5	1 kHz
2N5485	-0.5	-4.0	4	10	3.5		7	400MHz

NOISE:
2N5458 max 3 @1kHz
2N5485 max 2 @100MHz

I'd suggest to verify the info with the appropriate datasheets.
Found the above info on a chart floating around my HD:




What it all means I don't know exactly, ie which set of numbers is more key/germaine to the use in the pedal, but the numbers between the '58 and '85 differ a substantial amount.

Perhaps the BF245 A or B would be a better fit.
2SK117GR
2SK170


My knowledge is woefully lacking in this area.

 

[VanWhy]

Thanks for that chart and info. I figured I had to dig into it more. On paper I think I should I will go with the suggested transistors. Luckily Aion Fx has them in stock