Do I need to worry about RCA gauge

[Chris-toe-fur]

Do I need to worry about the wire gauge when running male to male RCA plugs from a DAC to amp? Or does it not matter over that short a distance? Is there anything else I need to look for, or will any function RCA cord do the trick?

 

[Sparky]

They're generally all the same size give or take. Unless you go for the exotic stuff.
It really doesn't matter though, to answer your question.

 

[KSTR]

Use quality coaxial cable with specified low shield resistance as that is pretty much the only parameter that really matters to get low noise/buzz.

 

[Sparky]

Use quality coaxial cable with specified low shield resistance as that is pretty much the only parameter that really matters to get low noise/buzz.

Is that a thing? Or is all that "low shield" stuff all snake oil?

 

[Fluffy]

If you plug it in, turn it all the way up, and don't hear any buzz, then it's fine.

 

[KSTR]

Any voltage drop along the shield that is caused by currents other than the (microscopic) audio return current appears as signal at the receiveing end, that's why shield resistance is so important with unbalanced cables.

 

[Speedskater]

Is that a thing? Or is all that "low shield" stuff all snake oil?

No, it's the real deal. for an analog RCA interconnect, a coax with a heavy low resistance braided shield is the most important factor. This is more important in rather long interconnects.
As for the center conductor, it could be very small, but then there would be mechanical reliability problems.

 

[KSTR]

If you plug it in, turn it all the way up, and don't hear any buzz, then it's fine.

Yep, basically that's it.

 

[Speedskater]

Any voltage drop along the shield that is caused by currents other than the (microscopic) audio return current appears as signal at the receiveing end, that's why shield resistance is so important with unbalanced cables.

Yep, it's about leakage currents from the AC power supplies causing hum & buzz.

 

[Martin]

To follow up. What about star quad rather than coax for RCA cables? Any issues there?

Martin

 

[Speedskater]

To follow up. What about star quad rather than coax for RCA cables? Any issues there?
Martin

A coax is a better choice. One small center conductor is all that is needed. It's a chore to connect all those wire in a small RCA shell.

 

[cjm2077]

To follow up. What about star quad rather than coax for RCA cables? Any issues there?

Martin

Star quad only helps in a differential cable. RCA are single ended. All of the noise picked up on the star quad would be summed in a single ended cable, as opposed to cancelled in a differential setup. But over short runs a single ended cable shouldn't be a concern as long as it has a decent shield.

 

[Martin]

Good to know. I have always purchased Mogami, Canare or Belden star quad cables for both XLR/balanced and RCA/single-ended usage. I'll use coax for RCA cables in the future.

Martin

 

[Sparky]

Can anyone post a link to a legitimate coax/RCA cable so I can understand the specs I'm searching for?

 

[Vincent Kars]

No.
To the best of my knowledge the "RCA standard" is about the dimensions of the plug, nothing else.
https://en.wikipedia.org/wiki/RCA_connector

 

[Martin]

Canare: http://www.canare.com/ProductItemDisplay.aspx?productItemID=80

Mogami: http://www.mogamicable.com/category/bulk/patch/

Martin

 

[KSTR]

Belden 8241F is a known-good classic: https://catalog.belden.com/index.cfm?event=pd&p=PF_8241F.
Note the "2.6 Ohm/1000ft " spec for the shield resistance (2.6mOhm per ft)
More choices (from Belden) here: http://info.belden.com/hubfs/resour...eater-and-high-end-audio-product-bulletin.pdf

 

[audiopile]

I'll admit that with both multiple turntables hooked up and digi speakers that only take RCA/SPDIF -I tend to pay attention to interconnect capacitance as a indicator of appropriate use both as feed from a MM cart and SPDIF cables. Connectors are worth paying attention to-( with a important caveat) -RCA's are cr@p -you will not find lab equipment with RCA connectors for their inputs -this connector was patented as a temporary service connection . In unbalanced interconnects -the low capacitance cables from Blue Jeans have worked fine for me -but I really try to run balanced wherever possible.

 

[Speedskater]

Unbalanced (coax) line level analog interconnects are one thing, digital interconnects another, musical instrument and some microphones are yet another and phone cartridge to pre-amp are a forth. The parameters that matter most for each type of cable may be different.

 

[cjm2077]

Unbalanced (coax) line level analog interconnects are one thing, digital interconnects another, musical instrument and some microphones are yet another and phone cartridge to pre-amp are a forth. The parameters that matter most for each type of cable may be different.

Any decent quality coax cable with a shield should be fine for analog interconnects at line level. It's the easiest job in the bunch. Digital interconnects need to be specified at a particular impedance (75 ohms) to deliver max signal level and not have reflections (a sort of distortion that reflects back part of the signal to the source), so the geometry is a bit more particular there, and depending on the speed you need to run things at the length and capacitance can become an issue. So for those, definitely buy coax that is intended for the application. Phono cartridges probably could benefit from a low capacitance coax as well, but the impedance (in terms of characteristic impedance as a transmission line not measured point to point impedance) shouldn't matter. I don't know of any mics or musical instruments that use rca connectors, usually musical instruments are TS or TRS phone jacks and the cable inductance and capacitance can matter because of instrument pickups aren't great source impedances and many commonly used tube amps aren't great input impedances. Mics are usually differential from what I've seen, but if they were run with just a coax cable capacitance definitely would matter, but again characteristic impedance wouldn't.