RCA Shorting Plugs

I used RCA caps previously. While they did make a difference, there was definitely a noticeable improvement going from caps to actual shorting plugs, like these:

https://www.hificollective.co.uk/accessories/rca-shorting-plugs.html

Adding a GutWire Ultimate Ground Cable to one of the RCAs took things even further, but that's another thread 😉

According to my calculations it’s unlikely that Cardas non shorting caps operate by preventing rf from entering the tiny diameter outlet/inlet. Maybe I’m not using the right dimension for the rf wave. I’m not claiming they don’t work, I believe they DO work. Ditto the unused wall outlets. Are they too small to worry about rf? RF wavelength at 800 Megahertz is about a foot. And at 10 GHz it’s more than an inch.

There are at least two types of RCA shorting plugs I’ve seen. One appears to directly connect the positive and negative sides, these are all over eBay and can be had cheap. Just a metal stamping with a plastic overmolding.

The other type has an actual resistor built into them and are more expensive.

Whats’s the difference, and are they interchangeable?

I just bought a bunch of the cheap eBay ones but am not sure they can be safely or effectively used after seeing the ones with the resistor.

Jaybe, regarding the safety of using shorting plugs which do not have a resistor (on inputs only, of course), the only situation I can envision in which that might be a problem is the one about which I stated the following in the thread Gdhal linked to in his first post above:

... some power amplifiers which provide both XLR and RCA inputs, the intent being that only one of those inputs would be used. In some of those cases the signal pin of the RCA connector is wired directly to one of the two signal pins (usually pin 2) of the XLR connector. So if the XLR input is being used in those cases and a shorting plug is put on the RCA connector, the output circuit of the preamp or other component providing the balanced signal pair to the amp would have one of the two signals on its XLR **output** shorted to ground.

And I suppose a similar situation could conceivably arise in the case of some subwoofers, if both RCA and XLR input connectors are provided for a given signal type (i.e., for either an LFE input or an input that is intended to receive a full range signal).

Also, as I said in that thread:

Consider the fact that the essentially zero ohm impedance presented to the input by a shorting plug is not greatly different than the very low output impedances (e.g., 10 ohms or perhaps even less in some cases) of some components that might be used to drive that input.

Finally, if which type is used makes any difference at all I would expect the kind that provides a direct short, rather than a resistor, to be more effective.  Everything else being equal, low impedance circuit points tend to be less susceptible to noise pickup than higher impedance points.

Regards,
-- Al

@almarg

In the related thread mentioned herein, I posted a question worthy (IMO) of your input (no pun intended) :) As that question has gone unanswered there, I thought I might pose the question here.

Might or should there be a theoretical or practical difference when using shorting plugs on an input dependent on the class of amplifier?

Reason I ask is that I’ve obtained and installed these:

https://www.amazon.com/Viborg-Audio-Stopper-Plated-Protector/dp/B017DH76VS/ref=sr_1_1?ie=UTF8&qi....

While I cannot detect a difference in the way my MF M6si (class B or A/B) noise floor emanates the slightest "hiss" or "sizzle" (no music source but volume cranked past 12) with or without the shorting plugs, I can detect a difference when I put them on the LFE input (class D) of my Golden Ear Triton Reference speakers.

Thanks, Al.

EDIT:

I'm aware of the difference in-so-far as the M6si I'm hearing the sound from the tweeter whereas in the T Refs the sound is from the woofer. So perhaps the shorting of inputs effects a particular frequency range more so than others?