Stability of cs amplifiers

[Seeker]

I've been fiddling with common source jfet amp circuits and I'm wondering how small I can make the bypass capacitor... It seems that in many circuits i've come across the value is 22uf.  How low can i go before stability becomes an issue practical world?  My source resistor is 5k... I'd like to drop my bypass capacitor to about 6.8uf for freq response reasons, I know this does work, but I'm wondering if there are issues that I may not be aware of.

Thanks

-Jason

 

[PRR]

You can omit the cap.

At some "low" frequency the gain drops. If you want deep bass you want a big cap. If you want low gain bass and middle with high-gain highs you can use a small cap (typ. 0.1uFd). If you want minimum THD and maximum flatness you omit the cap.

 

[Seeker]

thanks for the help PRR... I thought that the cap also served to prevent AC voltage swing from causing changes in Vds... was I off base?

 

[Seeker]

I think I found the rest of what I was looking for in horrowitz and hill, thanks again PRR.