# What does a"S" video cable carry?

**URL:** <https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416>\
**Category:** Factual Questions\
**Created:** [October 24, 2003, 10:44pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416 "2003-10-24T22:44:17Z")\
**Posts on this page:** 20\
**Page:** 1

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**Author:** ![InLikeFlynn](https://avatars.discourse-cdn.com/v4/letter/i/f19dbf/32.png) [@InLikeFlynn](https://boards.straightdope.com/u/InLikeFlynn)\
**Post date:** [October 24, 2003, 10:44pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/1 "2003-10-24T22:44:17Z")

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I understand that it carries the video on seperate lines and that gives great video but does it also carry audio?

Do I need the “S” video cable and a RCA cable (red, white, yellow) connected or does the “S” cable take their place??

a little confused:dubious:

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [October 24, 2003, 10:55pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/2 "2003-10-24T22:55:20Z")

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An S-video cable has two twisted-pair conductors. One pair carries the chrominance, or color, signal; the other carries the luminance, or brightness, signal. You’ll use the S-video cable for the video and a red/white audio cable for the sound. If your TV is a high-end unit, you may find you actually get better video using the yellow baseband video connector instead of the S-video. It all depends on whether the TV or the video source has the better comb filter (the circuit that separates the lumanance and chrominance signals).

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**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\
**Post date:** [October 24, 2003, 10:56pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/3 "2003-10-24T22:56:13Z")

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S-video only carries the picture. You will need RCA red and white cables for the sound.

The RCA yellow cable is for composite video, which is not quite as good as S-video. So use the S-video and R&W if you can, assuming the video source is something of high quality, like a DVD.

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**Author:** ![InLikeFlynn](https://avatars.discourse-cdn.com/v4/letter/i/f19dbf/32.png) [@InLikeFlynn](https://boards.straightdope.com/u/InLikeFlynn)\
**Post date:** [October 24, 2003, 11:18pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/4 "2003-10-24T23:18:16Z")

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Cool, Thanks

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**Author:** ![SkyBum](https://avatars.discourse-cdn.com/v4/letter/s/a88e57/32.png) [@SkyBum](https://boards.straightdope.com/u/SkyBum)\
**Post date:** [October 25, 2003, 2:17am UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/5 "2003-10-25T02:17:05Z")

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I knew damn well that Q.E.D. would already have this covered but I had to click the link just in case…

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**Author:** ![handy](https://avatars.discourse-cdn.com/v4/letter/h/b5a626/32.png) [@handy](https://boards.straightdope.com/u/handy)\
**Post date:** [October 25, 2003, 1:47pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/6 "2003-10-25T13:47:41Z")

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Most of my high quality s-video cables do not have three connectors, but 4.

That 4th connector is for the video part of the a/v connection. Weird.

e.g  
s-video  
audio  
audio  
video

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**Author:** ![Desmostylus](https://avatars.discourse-cdn.com/v4/letter/d/c57346/32.png) [@Desmostylus](https://boards.straightdope.com/u/Desmostylus)\
**Post date:** [October 25, 2003, 2:02pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/7 "2003-10-25T14:02:41Z")

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> [@](#):
>
> \*Originally posted by Q.E.D. \*  
> \*\*If your TV is a high-end unit, you may find you actually get better video using the yellow baseband video connector instead of the S-video. It all depends on whether the TV or the video source has the better comb filter (the circuit that separates the lumanance and chrominance signals). \*\*

Perhaps in certain limited circumstances, but generally it’s only things like DVD players and S-VHS players that have S-Video outputs in the first place. For those things, you’d always use the S-Video cable.

> [@](#):
>
> _Originally posted by handy_  
> **Most of my high quality s-video cables do not have three connectors, but 4.**

That sounds more like “general purpose” than “high quality”.

TVs capable of accepting both S-Video and composite video on the same input channel ignore the composite video signal if an S-Video signal is present.

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [October 25, 2003, 2:06pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/8 "2003-10-25T14:06:11Z")

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> [@](#):
>
> \*Originally posted by Desmostylus \*  
> **Perhaps in certain limited circumstances, but generally it’s only things like DVD players and S-VHS players that have S-Video outputs in the first place. For those things, you’d always use the S-Video cable.**

Again, it depends on the comb filters. The luminance and chrominance signals must be separated at some point. If your DVD player or S-VHS deck can do a better job of it than your TV, then use S-video. If not, use baseband video.

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**Author:** ![Tamerlane](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tamerlane/32/7602_2.png) [@Tamerlane](https://boards.straightdope.com/u/Tamerlane)\
**Post date:** [October 25, 2003, 2:24pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/9 "2003-10-25T14:24:18Z")

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> [@](#):
>
> \*Originally posted by Desmostylus \*  
> Perhaps in certain limited circumstances, but generally it’s only things like DVD players and S-VHS players that have S-Video outputs in the first place. For those things, you’d always use the S-Video cable.

Unless a three-socketed “component video” option is available, in which case that usually trumps S-video in terms of picture quality.

So in terms of picture quality:

1)Composite - worst ( but may still be just fine )

2)S-Video - better

3)Component Video - best

- Tamerlane

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**Author:** ![Desmostylus](https://avatars.discourse-cdn.com/v4/letter/d/c57346/32.png) [@Desmostylus](https://boards.straightdope.com/u/Desmostylus)\
**Post date:** [October 25, 2003, 2:47pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/10 "2003-10-25T14:47:00Z")

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> [@](#):
>
> \*Originally posted by Q.E.D. \*  
> \*\*Again, it depends on the comb filters. The luminance and chrominance signals must be separated at some point. If your DVD player or S-VHS deck can do a better job of it than your TV, then use S-video. If not, use baseband video. \*\*

DVD players don’t even _have_ comb filters. The Y and C signals are separate to start with, so there’s no need for a comb filter to separate them. And S-VHS decks are the really high-end stuff, there’s not much chance that the TV will outperform the VCR.

The only kind of player that’s likely to have a crap comb filter is a laserdisc.

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [October 25, 2003, 3:28pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/11 "2003-10-25T15:28:27Z")

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> [@](#):
>
> \*Originally posted by Desmostylus \*  
> **DVD players don’t even _have_ comb filters. The Y and C signals are separate to start with, so there’s no need for a comb filter to separate them. And S-VHS decks are the really high-end stuff, there’s not much chance that the TV will outperform the VCR.**

True, but still, I can’t say I’ve ever really noticed much of a difference either way, and I’ve had a LOT of equipment to play with over the years. The only thing that really makes a big difference, in my experience, are the component video connections found on many DVD players. Not too many TVs have this connection, and the ones that do are pretty pricey. Besides, my TV usually has a pretty good film of dust on the screen until I remember to clean it, so any benefit is lost right there. 😉

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**Author:** ![Desmostylus](https://avatars.discourse-cdn.com/v4/letter/d/c57346/32.png) [@Desmostylus](https://boards.straightdope.com/u/Desmostylus)\
**Post date:** [October 25, 2003, 4:08pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/12 "2003-10-25T16:08:09Z")

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> [@](#):
>
> \*Originally posted by Q.E.D. \*  
> \*\*The only thing that really makes a big difference, in my experience, are the component video connections found on many DVD players. \*\*

That doesn’t agree with my experience at all, and doesn’t even agree with what you posted earlier in this thread.

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [October 25, 2003, 4:14pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/13 "2003-10-25T16:14:48Z")

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Sure it does. I only stated that one might be better than the other depending on circumstances. I never said you could necessarily perceive the difference. If you can tell the difference, that’s great. In most cases, I couldn’t.

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**Author:** ![FatBaldGuy](https://avatars.discourse-cdn.com/v4/letter/f/ecd19e/32.png) [@FatBaldGuy](https://boards.straightdope.com/u/FatBaldGuy)\
**Post date:** [October 25, 2003, 4:24pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/14 "2003-10-25T16:24:15Z")

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> [@](#):
>
> \*Originally posted by handy \*  
> \*\*Most of my high quality s-video cables do not have three connectors, but 4.
> 
> That 4th connector is for the video part of the a/v connection. Weird.
> 
> e.g  
> s-video  
> audio  
> audio  
> video \*\*

Wrong.  
The 4 connectors are for Luminance (the brightness portion of the picture), Chrominance (the color information) and a separate ground for each. There is no audio information in an s-video connection.

From [Radio Shack](http://support.tandy.com/support_tutorials/audio_video/connector-svhs.htm).

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [October 25, 2003, 5:46pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/15 "2003-10-25T17:46:59Z")

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> [@](#):
>
> \*Originally posted by Fat Bald Guy \*  
> **Wrong.  
> The 4 connectors are for Luminance (the brightness portion of the picture), Chrominance (the color information) and a separate ground for each. There is no audio information in an s-video connection.**

**Handy** is talking about bundled cables with standard stereo RCA A/V cables and an S-video cable. Agreed that he used the term “S-video” incorrectly to describe the entire set.

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**Author:** ![Ike\_Witt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ike_witt/32/283_2.png) [@Ike\_Witt](https://boards.straightdope.com/u/Ike_Witt)\
**Post date:** [October 25, 2003, 6:46pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/16 "2003-10-25T18:46:51Z")

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> [@](#):
>
> \*Originally posted by Tamerlane \*  
> \*\*So in terms of picture quality:
> 
> 1)Composite - worst ( but may still be just fine )
> 
> 2)S-Video - better
> 
> 3)Component Video - best  
> \*\*

You are missing 2 things. Coax cable, which is right around the composite S-video sort of quality (I mention this because my sat. receiver has S-video and Coax outputs).

The new champ of picture quality is via DVI cable. It will use send an uncompressed digital video signal to the TV. DVI will be the cable of choice for HD signals down the road, and maybe even for DVD’s. The problems with DVI is that very few TV’s have a DVI input, and even fewer DVD and cable/sat receivers have DVI outputs. Not to mention that the cables run around $100 for a four foot cable. I have a DVI connection from my DVD player to my DLP TV and the quality is astounding, AotC looks exactly like it did in the theater.

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [October 25, 2003, 6:54pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/17 "2003-10-25T18:54:03Z")

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> [@](#):
>
> \*Originally posted by adam yax \*  
> **Not to mention that the cables run around $100 for a four foot cable.**

Is this an optical connection? If so, this price is ridiculous. I could make an optical cable for a couple bucks. In fact, assuming the connectors are available for small-quantity purchases, I can probably put together almost any type of cable for a few dollars.

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**Author:** ![billy](https://avatars.discourse-cdn.com/v4/letter/b/ecd19e/32.png) [@billy](https://boards.straightdope.com/u/billy)\
**Post date:** [October 25, 2003, 7:05pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/18 "2003-10-25T19:05:20Z")

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> [@](#):
>
> \*Originally posted by Q.E.D. \*  
> \*\*Is this an optical connection? If so, this price is ridiculous. I could make an optical cable for a couple bucks. In fact, assuming the connectors are available for small-quantity purchases, I can probably put together almost any type of cable for a few dollars. \*\*

You could put it together for a couple of dollars but you could not get it built for a couple of dollars. Take the couple of dollars for the parts, add the shipping cost of the parts, the packing costs of the completed cable, a portion of your morgage as storage fees, give your self a salary, health care, and all of a sudden, this two dollar cable gets very expensive per unit because of the low volume. Now, note that you have no competition from the large manufacturers and you will shoot for a 35% profit margin instead of 15% to keep the stock holders happy, and next thing you know, you are selling a $100 cable, even though your original goal was to sell it for $50.

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [October 25, 2003, 7:10pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/19 "2003-10-25T19:10:57Z")

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Hey, I just want to save a few dozen bucks, not go into business. If anyone else wants one of my cables, they can make it their damn selves. 😃

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**Author:** ![Ike\_Witt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ike_witt/32/283_2.png) [@Ike\_Witt](https://boards.straightdope.com/u/Ike_Witt)\
**Post date:** [October 25, 2003, 7:11pm UTC](https://boards.straightdope.com/t/what-does-a-s-video-cable-carry/209416/20 "2003-10-25T19:11:15Z")

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**Q.E.D.** , I am having trouble finding an exact definition of a DVI cable, but here is a link to [Monster Cable](http://www.monstercable.com/productPage.asp?pin=1868).

And, if you can make these, why didn’t you tell me before I spent the $100?

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