biasing jfets

[phsyconoodler]

When setting bias levels on jfets is it important to be right on or can you squeeze some more gain out of them with a little tweaking?
  Not being familiar with them I need to know if they are versatile like that or is it best to just stick withing the parameters.

Thanks in advance!

[Fresh_Start]

Are you using the jfets for switching or as gain stages?

Just trying to kick the can a bit,

Chip

[PRR]

> right on

"right on" WHAT?

I'm not aware of any "perfect" JFET bias.

> squeeze some more gain

Voltage gain is low. Optimization is like a vacuum triode. KNOW your load. Pick your "plate" resistor several times lower. For maximum voltage gain, adjust "cathode" bias for low "plate" voltage. Gain is max when the poor thing has no down-swing and low output, easy overload. So any practical amp sets the "plate" somewhat higher. Half of power supply is not a bad point. Indeed "4.5V" is universal among 9V FET pedal plans. This is not fussy, 4V or 5V is all the same, 3V is a bit more gain with abrupt overload, 7V is less gain with gentler overload.

[phsyconoodler]

I don't know what solid state stuff gives me shivers.It's so much like a tube in many ways.I was just wondering how forgiving they are when bending the rules like we do with tubes.
  It's all about tone and seeing how far you can get without a meltdown.
Thanks PRR!
  It's for gain stages in a pedal and they will have trimmer pots.

[JayB]

I don't know what solid state stuff gives me shivers.It's so much like a tube in many ways.I was just wondering how forgiving they are when bending the rules like we do with tubes.
  It's all about tone and seeing how far you can get without a meltdown.
Thanks PRR!
  It's for gain stages in a pedal and they will have trimmer pots.

They can be a little unforgiving when they break up. Kind of hard to find a middle ground in my experience but still loads of fun. The lower output impedance forces me to think differently, my noob experience. I've built a small pedal based around a marshall plexi with a tone stack. Sounds pretty cool and similar but not quite the same. I've been using 2N5484's lately, sound better to my ears. A J201 had to much harsh high end to the sound. But that could because of it being on a bread board and not in a proper enclosure with a better layout.