Should you cover your audio inputs?

A lot of audiophiles swear by the use of input shorting plugs on their unused audio inputs. Is this a good practice? What's it trying to accomplish and does it work?

[chadbarker]

Really! I think the more I watch audio videos the more crazy shit people come up with but hey if you hear a difference more power to ya! Have a good day Paul my man and be safe out there in Colorado.

[lambdastorm]

I bought two cardas cap covers just for fun. I didn’t notice any sound differences, but they do protect my rig from dust, so I’m happy.

[ThinkingBetter]

Great explanation Paul. Shorting plugs are only needed when an amplifier is poorly designed to allow itself to create noise by an unused inputs causing cross-talk into active inputs. If it can do audible cross-talk by just being unconnected, chances are that it can also cause cross-talk when having an actual signal. Get yourself a better pre-amp if you have such problem.

[varrol]

I cover both inputs and outputs with non-conductive caps. The reason is simple - after a year uncovered inputs/outputs get dusty and sometimes under bad conditions may even corrode - depends on sockets and air condition. Dusty and corroded contacts really degenerate the sound - you know that well from switches and potentiometers that need to be cleaned up once in a while.

[scottyo]

When I set up my lateset system I did many things including rhodium caps. Most of the things I have done make no difference in sound but they make things look nice and clean. Most systems I threw together and never care but the latest I wanted to take things to the next level.

[georgeanastasopoulos]

Today in the digital domain most of this audiophile fix up business seems to be bunk! Why cover up anything that is unused. If it is not to be used, best to leave it alone. I very much like Paul's reasoning. I have been listening to many of his lecturers, very logical, and practical.

[ahothabeth]

Tip: when you buy something that has cheap cables provided; cut the cable about an inch (2.5cm if you prefer) from the end and twist the signal and ground ( or earth if you prefer) together and solder the wire together.

That way you can see if shorting the inputs makes any difference to you.

I hope this helps.

I had a PS Audio III phono preamp and PS Audio passive volume control back in the day and loved my first taste of high end audio at a budget price. I lost them in a house move.

[mrpedrodrodriguezsr]

I have always covered unused connectors, but just to keep them clean . No other purpose !

[jamiermathlin]

You have a great approach to the world of High-End Audio, keep up the great work :-)

[dell]

Only shorting plugs made of unobtamium can be counted on to give you the lowest noise floor. I do agree unused phono inputs should be grounded because of the very high gain the circuitry has.

[judgegixxer]

What!!!! I just paid $600 for a pair of Platinum diamond powder infused shorting plugs! The guy at the mall kiosk said they're the hot ticket.

[andydelle]

I owned a Sansui amplifier in the 70s, I think it was a AU7700? It had two phono inputs and they provided a set of shorting plugs if one phono input was unused. Made sense in that application but for line level signals it makes no audible difference electronically. But for dust and dirt, it's not a bad idea. Of course just make your own with cheap RCA plugs. No need for "high end" shorting plugs and just a stock unshorted RCA plug will keep the dirt out just as well.

[timw.]

Glad I watched this because I bought caps for all of my inputs and outputs on my streamer/DAC/amp 😬 I had no idea you weren’t supposed to use them on the outputs! Had them on like this for months and thankfully my equipment still works...for now.

[mat.b.]

Thanks, just bought some shorting plugs from this suggestion. While you say it doesnt make a difference for most, I think it will help on my vintage receivers that have a lot of noise and channel cross talk. Worth a shot at least!

[backyardwindow]

Paul seems like an amazing guy. I want to be like Paul. Thanks for the content!

[johnmarchington]

I don''t know about shorting plugs but what I have done is buy a packet of little plastic/nylon covers that I place over the unused RCA input sockets to keep the dust out.

[SimonKinsella]

Here's a test you can try - set your amp to normal listening volume and compare the noise level of an unconnected _selected_ input when it is shorted vs when it is open. Note the difference. Now, if that same input is no longer selected, that difference will be scaled down by say >100dB, depending on how good the switch is. That's the benefit you're chasing, multiplied by the number of unused shorted inputs you have. Good luck!

[aussieexpat]

This is an easy test, put a strong sine wave or something on line A. Turn on line B while shorted. If you detect anyting like the sine wave instead of nothing, then there's a difference.

[BrotherNkosi]

Actually it a big difference FOR THE WORSE!! MY Chi-fi Audio GD sound was negatively affected when I shunted the un used RCA inputs. I was using the balanced and shunting the RCA had a clear on off affect that one need not have a golden ear to hear, .

[stevebrown]

Back in the day, the rotary input selector switch often had a "grounding" wafer that effectively shorted to ground all inputs that were not selected. This helped reduce crosstalk. For example, you have a tuner plugged in and a turntable, signal from the tuner can bleed into the phono input and can be audible in the background. I'm guessing PS Audio's relays have a similar arrangement that shorts unused inputs to ground, I'd be surprised if they didn't.