Aaron Gould

RCA wall jacks for component video?

I'm installing six runs of cable ("RG59SD" from Liberty Wire & Cable - libertycable.com) from one side of a room (computer) to another side of the same room (A/V rack). The room is being finished by myself, so these cables are fed through drilled wood studs along the wall. These cables are 75 ohm, and used by installers at my local high-end A/V retailer.

Of these six cables, three are for component video RGB. One is for digital audio (SPDIF), and two for Left/Right analog audio. Each of these runs will measure 20 feet (wall jack to other wall jack).

Now all of these cables will have RCA type ends (crimped on by myself), as all these cables types normally do. As it stands, I will just hang these ends out of a wall-plate specifically intended for this. I will leave about three feet of slack so that the ends may reach my equipment.

Here's the thing -- I would rather this have a more finished/integrated look, and install a 6-gang plate on the wall. Into the back of this plate (inside the wall), the six cables with RCA ends will plug in; and on the front of the plate, I simply plug in my A/V cables to my equipment.

Home Depot has 6-gang modular plates from Leviton that I can assemble using RCA to RCA modules to create a jack like I described above. So I'd buy two 6-gang wall plates, and 12 RCA to RCA modules (same combination at both ends).

The burning question is: are these Leviton-branded modules (at $6 CDN a piece) too low-quality to use for this set up? I would assume the audio portion would be ok, but the video? Perhaps there is a better way to do the ends? Keep in mind that I don't need super-incredible quality, and can't spend a lot of money. This is just for connecting my computer's video and audio to my TV/stereo across the room. It's for games.

Thanks for any help, hopefully you made it this far and still understand what I'm asking!!

Bob McElfresh

To start, run the wires through electrical outlet box's, buy blank wall-plates and drill holes/thread the wires through before adding the connectors. You want an un-broken path if possible and this will still give it a nice look

Later, if you want you can cut the wires off at the outlet box and install face-plates with RCA jacks.

You should know that the RCA plug/connector is kind of bad for maintaining the 75 ohm impedence that video signals want to see. BNC connectors are superior for the signals, but look crappy/industrial.

Aaron Gould

Thanks Bob, I appreciate the response!

I'll certainly leave the cables untouched for now. I understand that the video needs to maintain the 75 ohm impedence... is this the same for audio cables? Or are audio runs not as sensitive as video?

DaveKahler

If the audio is digital (which you said it is - S/PDIF), it should maintain 75 ohms. Normally I wouldn't care too much about the audio, since audio tends to be insensitive to cabling, but something about digital audio makes me want to make sure the cable is right - there's just so much information in that one cable!

Bob McElfresh

Analog Audio cables are typically made with 50 ohm coax. But 75 ohm works just fine.

Digital-Coaxial cables should be 75 ohms. The people who wrote the SPDIF spec had a video cable in mind.

Sometimes bundles of cables with markings for Left/Right/Video are all made with identical 75 ohm coax. They just use different markings on the RCA plugs. But once people got wise to these and started using them as cheap component video cables, they changed to different coax for the audio.

Aaron Gould

Interesting, I never really though of all these cables in terms of impedence. So much to learn still. Heck, up until the last year or two, I've just used cheap (and very low guage) cables from Radio Shack type stores. And with varying number of adaptors/extenders in between! Luckily that habit has ground to a halt.

Since I have this roll of uncut 75 ohm RG59 cable from my A/V retailer, I'll just cut all six strands from it. Even though the Left/Right analog audio only need 50 ohm, 75 can't hurt right?

Thanks guys!