Input /output caps


Have seen for some time now that some manufactures use "sheilding" caps on the unused input/output jacks in an effort to reduce emi/rf and enhance sonic benefits. My question is has anyone one been using them and if so WAS there a preceviable sonic difference with them in use (as I realize that it could be subtle)? Becuse Cardas caps aren't that expensive and could be an inexpensive tweak for me to try then. Thanks for the input.
rsjm80
I have been using them (Cardas caps) on my system for years. I won't tell you that I hear any difference, but I don't seem to have any EMI-RFI issues either. But one of the benefits that I like is the clean jacks. No dust is getting in through the jacks and I find that reassuring.
It's better to use shorting plugs on your unused inputs. That way you keep the jacks clean AND you ground the center pin of the jack. What does that accomplish? Two things:
A.) It's then impossible for the jack to pick up RFI in the first place, and
B.) You won't hear a 'pop' as you rotate the source selector through the unused input(s) as sometimes occurs with certain preamps.

On unused outputs, you could use Cardas Caps, but caps on outputs don't have to be metal and are just for protection, it's much cheaper to cover them with those cute little red or black vinyl caps ;-)
I found great, inexpensive shorting / non-shorting RCA caps on eBay. (They have a threaded removable center pin.) $12 for 10, $18 shipped. Just search "RCA caps". I received them within 2 days and they work as designed. No affiliation. I have not noticed a difference but what the heck, you can't go wrong for the price.
Thanks for the input everyone, I'm always looking for an inexpensive upgarde or improvement, this helps still again for me.
Nsgarch is correct. I used to use the Isoclean shorting plugs on the inputs to my preamp. They worked very well , although expensive. I recently switched to the High End Audio "shorties" plugs. There was a very noticeable difference for the better (a more analog or natural sound). They are also less expensive. High End offers a 14 day free in home audition. I was skeptical, since I really liked all of the Isoclean products I've ever tried, but these really work.