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is there any difference in sound performance if i use a normal RCA analogue interconnect as a digital cable? Is it true that a digital cable is designed specially to handle digital signals, hence using a analogue interconnect is not recommended?
 

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There may be an impedance difference. Also a bandwidth difference. In general you will want a "digital" cable, but the analog cable might work just fine. Try it and see.


If you do buy a digital cable, don't spend much. They're not magic.
 

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the specs for digital coax require a 75ohm cable. Analog audio does not require any specific impedance (though it may very well be 75ohm anyway). Keep in mind that video also requires 75ohm coax cables, so for a digital application, you should use any coax that's labeled 75ohm, digital, or video.


If you use something that is not this impedance you may suffer dropouts, etc. Doesn't have to be an expensive cable, any decent rat shack video cable or digital cable will do fine, they should be 75ohm.
 

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i was actually thinking of the same thing as well but i wanted to use a high quality digital cable as an interconnect. does anyone know if i will get better performance doing this?
 

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Quote:
i was actually thinking of the same thing as well but i wanted to use a high quality digital cable as an interconnect. does anyone know if i will get better performance doing this?
It will work fine. As I explained, the only thing that a "digital" interconnect is, is a regular coax that is 75 ohm, just like a video cable. As noted, analog interconnects for audio need not be any specific impedance, so anything will work fine. Whether it will work better depends on the quality of the system, the quality of the other cable, etc, and whether you hear any differences or not.


Tony: your answer is insufficient, and likely to cause confusion. Please refer to my explanation. It is not completely untrue, though the wording points to that conclusion.


As I said, digital interconnects, and video cables both require 75ohm coax due to concerns with reflections in the wire due to impedance mismatches if you use cables of a different impedance. In this way, cables sold as "digital coax" will be 75ohm. However, there is nothing unique about this 75ohm cable from other similar-build quality 75ohm cables. For proper performance, you should use a 75ohm cable for digital interconnects. Whether that cable is labeled "digital" or is labeled a video cable, is irrelevant. The point is that it needs to be 75ohm.


Audio interconnects need to be 75ohm, so they may not be. You should not use analog audio cables for video or digital audio unless you know that they are indeed 75ohm and are labeled as such.
 

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My answer is sufficient and to the point.


YOu keep claiming that 'digital interconnects' are 75 Ohm coax cables? What does DVI use? How about ethernet? Neither use 75 Ohm coax, although thinnet used a 50 Ohm coax cable, and token ring a 93 Ohm coax...a lot of 'digita'' devices use 110 Ohm twisted pairs.

In any case, there is no such thing as a digital cable, nor can one be optimised for 'digital' signals.
 

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tvtech, I'm sorry but you are wrong.


digital coax standards require a 75ohm coax.


Would you similarly toss out the need for 75ohm coax for video applications? I don't think so.


in-wire reflections are not a problem for analog audio frequencies since you can't hear things in the mhz range. It definitely is for video. And while probably less stringent with SPDIF, you may experience dropouts if you're not using a 75ohm cable. It doesn't cost anything more to get the right cable, there's no excuse not to have the proper kind.
 

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I think you missed the point of the post. No-one has said that a digital coax connection doesn't need a 75 Ohm cable, it's just that there are many other 'digital' interconnects that require different types of cable and characteristic impedance, not just the 75 Ohm coax.
 

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.... and let's not forget wireless digital interconnects!!! AIR!!!


Why are some people so darn picky?

Sheesh!


From now on... NEVER use the term 'digital interconnect'! It's too general.

Be specific or feel the wrath!
 

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Does it not get a digital signal from point a to point b?


You started with specifics.

(and I do know that it is converted to an RF signal.... yada, yada)


Getting to the basics... even copper as an interconnect is not a 100% digital waveform/signal end to end.
 

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You are correct 'wise one'... it is an RF signal. Depending on power and frequency, it can pass through air, walls, a vacuum, and between your ears!


Why is that you always troll just to spout your 'perceived' knowledge. Do you get a kick out of 'nit-picking' everyone's post? Does that make you smarter? Does it provide some type of self gratification?


If you are so talented... why aren't you at MIT doing reseach to make the world better?
 

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What the heck are you guys talking about!?


I took the discussion, as it ALWAYS is, to be about SPDIF standard digital coax for audio. That's it.


As such it's VERY simple. Use a 75ohm cable. Whether it be one sold as "digital" or not, just get a 75ohm cable, and you're set. It's not rocket science, or a confusing mess of other cable types and transmission methods. sheesh.
 

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I'm with you Chris, it really is pretty simple until someone wants to make it difficult.
 

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Quote:
Originally posted by Ratman
.... and let's not forget wireless digital interconnects!!! AIR!!!


tvtech1:

That was meant 'tongue in cheek'. You are too literal.

Why are some people so darn picky?

Sheesh!


From now on... NEVER use the term 'digital interconnect'! It's too general.

Be specific or feel the wrath!



This was not meant in anger. Just trying to make a point in regard to your short retorts that are always challenging, overly critical and condecending.
 
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