RCA Shorting Plugs


I am coming to the conclusion that success in home audio reproduction is largely about lowering the noise floor. There are so many different types of “noise”, from so many different sources, that we only really “hear” by their absence.

I have had caps on the unused RCA inputs of my ASL passive autoformer preamp, ever since a friend suggested them way back. I recently got some actual shorting plugs (with resistors), from Hifi Collective in the UK, to replace them. I was surprised by how much difference they made. Transparency, resolution and musical flow all increased, along with the “realness” of instruments and voices. There is also more sense of the space around them.

I know some preamps short the unselected inputs, but, if yours doesn't, these shorting plugs are inexpensive, and definitely worth trying.
tommylion
I just installed a raft of Cardas non shorting caps all of which are in my LG HDTV and LG Blu Ray player. But what I really wanted were the new Telos caps that are really cool looking and undergo some special infrared treatment, alas they’re out of my price range.
shorting unused inputs **can only be advantageous, even if only theoretical** (electrical theory).

This is pure BS, because if they’re not used they are not connected to any active amplification circuitry!!
The only advantage they have is to keep dust out????

Cheers George
@elizabeth 

My F5 has a 47kR between the input pin and ground internally. If the unit is wired like that shorting plugs are pretty much useless. That's all you really need to avoid noise and ocillation. 
Non shorting plugs prevent rf from getting inside the component. Dust actually won’t go into unused outlets/inlets unless there’s a good crosswind. 😀  Yeah, I know what yer thinking: The holes are too small for rf to get into them. Just like rf gets into unused wall outlets, including non audio outlets. Same idea. RF is like Chickenman. He’s everywhere, he’s everywhere!! 🐥
Furthermore, it’s quite possible that shorting caps - at least in some cases - simply do what non-shorting caps do — prevent RF from entering the component and wreaking havoc on the audio signal and everything else.