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View Full Version : COMPONENT audio leads different from regular RCA audio cables?




netdog
Mar 29, 2007, 07:40 AM
I bought proper component cables (R/B/G) for the video out of my AppleTV, but figured for audio I could get back with the normal RCA audio leads that I had already.

My picture is fine, but I can't seem to get the sound. Is it that I am using the wrong cables?

Also, if I use an HDMI -> VGA adapter instead, will sound come accross that path?



Passante
Mar 29, 2007, 07:54 AM
RCA audio cables transmit component video. Neither component video or the HDMI to VGA transmit audio. You need to run audio cables for both.

mkrishnan
Mar 29, 2007, 07:56 AM
1) Yes, both component and analog two channel audio use standard RCA cables. You should have a total of five RCA cables connected to the Apple TV -- three for video that go to the three video plus, and two for audio that go to the two audio plugs. Make sure that you're plugging the two audio outputs into analog audio inputs and not into a Dolby Digital input that uses a single RCA cable.

2) HDMI->VGA -- Maybe, but probably not. HDMI can (but does not always) carry sound. VGA does NOT carry audio. So at best, the converter will have on the far end a VGA plug and audio outputs, and you can plug those audio outputs into the audio ports on the receiver / TV / whatever. The VGA cable will not carry an audio signal, though.

Does that help? If not, please provide specifics: what kind of device are you plugging the audio into? Receiver, TV, etc, etc? If TV, are you sure you're using the right set of audio inputs that go along with that set of component cables?

JonHimself
Mar 29, 2007, 10:20 AM
1) Yes, both component and analog two channel audio use standard RCA cables. You should have a total of five RCA cables connected to the Apple TV -- three for video that go to the three video plus, and two for audio that go to the two audio plugs. Make sure that you're plugging the two audio outputs into analog audio inputs and not into a Dolby Digital input that uses a single RCA cable.

I feel dumb for asking this, but: You're saying that if take a basic RCA cable (just like a red and white one that I've had for years) and use an additional RCA cable (using just one of the two plugs on this cable) they can substitute for the 3 component video cables? (Typical Blue Red and Green). That sounds like what you're saying but I never knew that was possible, I assumed they were different cables...

mkrishnan
Mar 29, 2007, 10:26 AM
...if take a basic RCA cable (just like a red and white one that I've had for years) and use an additional RCA cable (using just one of the two plugs on this cable) they can substitute for the 3 component video cables? (Typical Blue Red and Green).

Yes that's correct. And yes, I have done so. It's nice to have higher quality cables, but you frequently cannot tell the difference between a "component" cable and those cheap red/yellow/white three plug AV cables sold for SDTV. What I have right now is (I think) my DVR plugged in via cheap cables and my DVD via "component" cables. I use the DVR more but the difference was mildly noticable (some sort of shimmery artifacts) on the DVD, whereas with the DVR I could not tell a difference, for whatever reason.

notjustjay
Mar 29, 2007, 10:32 AM
I feel dumb for asking this, but: You're saying that if take a basic RCA cable (just like a red and white one that I've had for years) and use an additional RCA cable (using just one of the two plugs on this cable) they can substitute for the 3 component video cables? (Typical Blue Red and Green). That sounds like what you're saying but I never knew that was possible, I assumed they were different cables...

I think technically they are different (50 ohm versus 75 ohm nominal impedance? anyone?) but in the real world it works fine.

Avatar74
Mar 29, 2007, 02:00 PM
I think technically they are different (50 ohm versus 75 ohm nominal impedance? anyone?) but in the real world it works fine.

Most if not all Coaxial RCA should be 75 ohm. Cabling manufacturers don't typically even make the cables specially for any one purpose. They buy bulk 75 ohm from a cabling vendor. Then they buy the interconnect plugs from another vendor. Then they solder the interconnects to the cable, package and rebrand it and sell it at a ridiculous markup.

If you're in England I'd look up Van Damme Cable (vdctrading.com). I live in the states, but I've heard good things about them.

EDIT: Hmm... after looking at VDC's site it appears that British RGB Component video are in fact 50 ohm. The US uses a different Component video standard, Y/Cb/Cr, and 75 ohm coaxial RCA tends to be the standard here. So I dunno... I would suggest picking up some books on PAL standards. DON'T go into an A/V store because they'll misinform you either knowingly or unknowingly.

Diode
Mar 29, 2007, 02:06 PM
Most if not all Coaxial RCA should be 75 ohm. Cabling manufacturers don't typically even make the cables specially for any one purpose. They buy bulk 75 ohm from a cabling vendor. Then they buy the interconnect plugs from another vendor. Then they solder the interconnects to the cable, package and rebrand it and sell it at a ridiculous markup.

If you're in England I'd look up Van Damme Cable (vdctrading.com). I live in the states, but I've heard good things about them.

And you should look into bluejeanscable.com in the states^^

notjustjay
Mar 29, 2007, 03:15 PM
And you should look into bluejeanscable.com in the states^^

Heard good things about them. I'm partial to Monoprice.com, myself.