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[Mr Ed]

spillage what country are you from?  In the US a coaxal cable is used for RF transmissions.  Of course other cables are made "coaxially" but a coax cable is always referrring to the 75ohm cable/antenna/RF cable.

Recently, they have started referring to a single RCA cable for digital audio as a coax as well.  Just to help confuse the consumer.  

Also, I don't understand the debate regarding digital audio cables.  If the connection is good you will get sound, if not you don't.  Because it's digital there isn't a concept of signal degredation.  The only issue with digital might be synchronization.

[spillage]

Sparkac,

I may be considered anal here, but to me the slang for RF is ‘Coax’ not coaxial. Coax seems to be the adopted name for a cable that is designed primarily for use with TV/SAT. I am used to giving the proper name for ‘coax’ cable to electricians/installers etc to make sure they don’t install the crappiest RF cable they had on the van. One ‘coax’ for RF TV is not the same as another. Anyone using the standard patch cable supplied with a VCR etc should chuck them cause they are generally of very poor quality with poor shielding a massive reflections. Since I have started- a reflection is a portion of the intended signal being bounced or reflected back up the cable. This causes all sorts of unwanted issues, ones you can see. Proper cable can eliminate this.

I cannot find my reference to optical/video, so I will retract the comment.
‘Coax is cheaper’ my correction, yes you did say that. I would disagree and say optical is cheaper. You can buy some really shite plastic OPTICAL cables for less the £3.00 ($4.86) here.

Mr Ed

I live in the UK and like you guys have coax cable for TV/SAT use. It’s called coax here as well. My problem with Sparkac using the term ‘coaxial’ was simply that some many cables are coaxial in construction. If a guy walks into a local shop to buy an expensive cable and sees on the box that it says it’s a coaxial cable, he may think, cause he has read it here, that its not good enough. That was my point. Maybe I could have worded my response a little better.

I don’t profess to have all the answers but I know, (fact) that different cables used for a coaxial digital connection make a big difference to the perceived sound quality. When I used to work in the audio sales industry, I only do bespoke HT and multiroom now, I had on loan from Nordost a £400.00 Moonglow. It was bloody amazing. I have since tried a number of cables mostly self built to experiment. I am using an 80cm piece of all silver 75 ohm high speed data cable. It too is better than any £100.00 cable I have used before. I believe the reason is ‘jitter’ or timing errors. A better cable is able to time better. 0’s and 1’s are unchangeable but I guess timing and sync are. Incidentally I have tried many optical cables too. I have to say that above £40.00 I could hear no difference.

[sparkac]

ok spilage, we are talking about consumers who have no idea about cable, NOT professional tv studio technicians.  I appreciate your help but it isn't needed at this level  

QUOTE

(fact) that different cables used for a coaxial digital connection

I don't know about the CONSUMER tvs in the uk but the ones in the US don't have coaxial digital connections, again this is a tutoirial for consumers, don't go off topic

QUOTE

I may be considered anal here

yes... you definatly are

And thank you Mr ED  

This post has been edited by sparkac: Oct 22 2003, 03:30 PM

[kcarlen]

After reading the initial infomation, I was impressed to think that someone has taken the initiative to do extra work for free.  Hats off Sparkac.  
However after reading the replies I am almost embarrassed to think that you guys are acting like children...god knows...maybe you are this day and age.  Give the guy a break man!!  He has developed some constructive information that although is maybe not 100% accurate.....is damn good work.
I should further comment that I am an Electrical Engineer, and appreciate good information.  I also appreciate constructive critisizm.

Spillage, you need to lighten up.  Get off your A$$ and thank the people that help out others....don't try to make them look small with you somewhat "untechnical" responses.

[spillage]

Sparkac, looks like this posting has caused some concern. I hereby apologise if my reply in anyway made you feel insignificant or small. Your efforts have been well recieved by nearly 300 fellow owners. It was never my intention to cause any grief. My policy has always been say what you think not what they want you to say.

Kcarlen. I worked as a BMW technical diagnostic technician for 10 years, have 4 years of electronics schooling and 6 years as a Home Theatre Consultant. My methods don't f**k about. My approach may have been wrong, but my intentions were good.

I hope this apology settles the matter.

Good job Sparkac.

This post has been edited by spillage: Oct 30 2003, 12:00 PM

[sparkac]

thanks kclarlen, that was nice of you  

[Wiz]

This is a great idea, in a simple way lay out the basics of cables.

No pun intended, but some of the things I saw was somewhat confusing.

Coaxial - adj : "having a common axis" [syn: coaxal]
http://dictionary.re...earch?q=coaxial

Coaxial cable - this is ONLY the description of the physical design of a cable, saying it is a cable that have one axis (or "core" if you will). It has nothing to do with what signals the cable is being used for. (RF/Composite/Component etc)

This has been said allready, just not in much detail.
The fact is that all cables in the original post except the optical fibre cable ARE coaxial (ie "having a common axis")

So if you want to buy a cable made for transporting "RF" you ask for a "RF-cable". This way its easy to end up with a cable that is the right one.

As far as cable for digital audio goes, it doesn't really matter  what cable you use as long as it is capable of transporting digital data (ones and zeroes as usual).
Optical is superior as far as being resistant to magnetic and electric interference and can also be used over very long distances.
In reality, digital data as slow as in this scenario is transported well by whatever cable you might have around the house. Simply put, if it works it works well

Rgds!

[havocaose]

from what ive heard..

analog means a cable where the electricity is lowered or raised to create a wave patternt that the recieving unit interperated.. becuase its a wave pattern it can be distorted and usually offers decreased quality.

digital (like toslink) is where light or electricty is shot through in extremly short bursts.. when there is electricty or light its interperted as a 1.. when theres no electricy or light its a 0.. becuase its either there or not thier signal cannot be distorted.

[Wiz]

The principle is sort of like that yeah.
Or rather it "can" be, but its doesnt "have to"

_Very_ generally speaking.

Digital information is allways communicated in a predetermined fashion. What I mean by that is that the sender of the information knows what the reciever interprets as being a "1" or a "0".  So it doesn't really matter what the actual "1" is, what matters it that it is pretedermined.

If that is the case, any information not representing a "1" or a "0" can simply be discarded or ignored.


In real life a good comparison would be your standard light switch compared to a dimmer.
Digital would be the switch turning it on or off, no other setting than that. Analog would be like the dimmer where you can choose any lightintensity from off to on.

The Xbox and its digital audio output used a protocol called "SP-DIF" (SONY-Philips Digital Interface Format) and that protocol is understood by both the xbox and your sound system. It is basically a standard that describes in detail how the information is to be communicated. The upshot of having the standard (which has been around for a long time in professional equipment) is that you can plug more or less any digital audio device into any other digital device and it will understand the data being communicated to it. Logically connecting a cable from say a CD player to another CD player is not going to make anything useful happen as both are output devices, connecting a CD player to a SP/DIF input on your computer on the other hand is more useful since it knows what to do with the information it gets. The sender can send a copy protection order also, so even though your computer might understand it, it might not let you record the data because of this.

SP/DIF as a format when it comes to xbox is a very very slow communication (compared to, say, a gigabit network fibre)
And it takes a lot of interference before the information will get corrupted. The SP/DIF on the xbox will transfer any kind of audio data, everything from mono sound to multichannel audio like AC3(called Dolby Digital nowdays) or DTS(Digital Theater Systems)
Ideally a 75ohm cable of coaxial design, or a fibre cable is used to transport the SP/DIF signals. But chances are that any old cable will do the trick really...

To sum the above up. The above is very general information, it is possible to deditace a lifetime or two to details about this kind of stuff. But if you know the above, you will still know more than most "normal" people you will ever meet And hopefully you won't be fooled into buying "exotic" cables spending all your money (that you could instead use to rent some movies or something)

Hints about ready made cables.
Expensive cables - You ARE getting ripped off.
Exotic cables - (see above, as they usually happen to be expensive, and there are still people around who thing something is better if its also more expensive)
Exotic materials in cables - basically stay away from these, they cause more harm than good, and thats a scientific fact.
Cheap cables - IF you use them for what they were designed for you probably have the best option possible

DIY cables.
Exotic materials - Don't go there, waste of money.
Copper - If its electric this is the material of choice
"100% Oxygen free copper" - (see above) This has been around for a long time and is today more or less the only type of copper you can buy world wide. Some people will say thats not the case, what that tells you is that they have no idea what they are talking about

Optical Fibre - There are two major materials here, the core is either some type of fiberglass fibre or made out of plastic. For the DIYer plastic is so easy to work with. Just cut off with a sidecutter and snap-on a connector. Takes about 1min or less to make a cable. Fiberglass fibre has better optical properties than plastic but requires special (expensive) tools to make the cut clean.

What type of cable to buy?
Visit a store that has a WIDE variety of cables, see your local tv/radio repairshop, they will probably know where to find a good store (as they likely buy their own cable from them)

Things you need to know (as a good sales person WILL ask you these question BEFORE he recommends a cable)

How long will the cable be
What kind of signal is it going to transport
Any specific color (trust me its not as stupid a question as it might seem actually
What connectors do they offer, go for one that is easy to work with, preferrably a sturdy one too.


Hope this helps

[jamal]

I have a question about:

Scenario 2
You have a peaty big TV, 25in to ~40in.
Use s-video or composite. Stay far away from coaxial
If your TV has component, you will see a change but not a big one. If you are a heavy gamer a component cable will help

Now question...

I have a 27 inch Toshiba flat screen TV that has s-video, composite and component video in. This TV is NOT HD and only works in 480i rez.

In order to use the HD Pack, I have to go into the MS Dash turn off 480p, 720p, and 1080i which puts the HD Pack into what 480i?

Would this be better then the s-video? I know when I tried my friends HD Pack, I didnt visually notice a diffrence.

I'm trying to decide if I should buy the HD Pack, S-video pack or stick with the RCA's the XBox came with. I know you said the componet would be better but I didnt notice a diffrence so then I wouldnt notice a diffrence with the S-Video eather would I?

[ngarutoa]

Jamal - if ya tv only accepts 480i (non HD), jus run s-video, the detail should be about the same as the component, if the component isnt running 480p/720p etc.
But if u already have the Component cable etc & are happy with it, then sweet az.

[hydraulix]

QUOTE

Its disadvantages are low picture quality and mono sound (half of stereo).

incorrect, it carries a stereo L/R signal, the thing is, most older tv's with this type of connector only have 1 speaker in them.

[mrbojanglez50]

spillage, you seem very knowlegable.  where does a BNC video cable fall on the low end to high end cable chart?  Im guessing its better than VGA and component.

Thanks

[Wiz]

BNC is the name of the connector itself, it has little to do with what signal is being handled by the cable it is on.

BNC connectors are _usually_ used in higher end equipment such as projectors. But that kind of eqipment uses them from everything from composite (all video signal in ONE cable, usually a coaxial type) to RGB and Component (3 to 4 or in some cases even 5 cables)

Coaxial is the type of cable, BNC or RCA is what the connectors at the ends are called (or "plugs" if you will)

In order of video quality the list is this, from worst to best
1. RF (a radio signal transmitting video, if you amplify it you have your own TV station.
Cable: one Coaxial cable
2. Composite video, a "composite" or "mix" of all the separate signals that is needed to make a video image.
Cable: One Coaxial cable
3. S-Video (has nothing to do with SVHS that is a VCR standard)
Cable: Usually Two coaxial cables if the cable is of better quality
4.Component,  components of the video are transmitted by individual Coaxial cables
Cable: Usually 3 coaxial cables
5. RGB with sync, the components of the video signal are transmitted separately (more so than for component video)
Cables: Usually 4 coaxial cables
6. RGB with two separate syncs (I only mention it here, since the signal is not available and have to be extracted, which is basically what your TV/Projector does anyway so it wont add to quality unless you can tap into it in the xbox someplace).
Cable: 5 separate coaxial cables.



All the above is the way it normally is done, cable manufacturers make cables in all sorts of ways and sometimes bundles signals in special cables (usually a lot of coaxial cables bundles together in one single cable)

Generally the quality gets better the more separate signals you can find (in the hardware on the xbox in this case) before they gets mixed into more complex signals. At the reciever end, the less decoding you need to do  to separate all the signals again (for showing) the more of the original quality is kept.

Coaxial once and for all is nothing but a cable design, as you see above it is the most commonly used type of cable used for ANY audio/video signal. Yes the analog audio is also using coaxial cable for the most part.
Coaxial means "common axis" nothing else.

Hope the worst->best list works as a guide to what you could use in your own xbox cabling. The above is ONLY about the cables, nothing about where you live and what TV system you have there, or any practical issues like if you are able to actually find an input on your TV/Projector or whatnot.

Rgds,