Audio input question

[Mark Amundson]

The prefered RF rejection circuit used in alot of pro gear is a
series 470 to 1000 ohm film resistor followed by a 100pf to 470pf
to ground; selection depending bandwidth required. The RC junction
is then sent to the standard 100k ohm input. The 0.22uf can be used
for decoupling from the RC junction. Ferrite beads are sometimes
used in series with the 470 to 1000 ohm resistor to roll of the
radio frequencies quicker.

Mark Amundson,
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>1) For RF rejection, use a 100pf cap on all ins and outs to ground. Don't go over this, >or you may have op amp
>drive problems.

>2) Use 0.22mfd for audio AC inputs.

>Paul Schreiber
>Synthesis Technology
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        To reject RF crap in an audio input jack, approx. what value 
cap should I use to ground, and what (if anything) should I use in the 
audio path to buffer the input a little? (.01uF cap is in at the moment, 
and no cap to ground.) Will a teeny cap + pot here work alright to 
buffer/decouple it a bit and allow level control? If so, what value cap 
do you recommend? Not terribly urgent/important, just curious. =) TIA-

        Jason