General question about digital audio

Discussion in 'AV Receivers' started by Andrew_G, Aug 11, 2004.

  1. Andrew_G

    Andrew_G Agent

    Joined:
    Jul 10, 2004
    Messages:
    33
    Likes Received:
    0
    Trophy Points:
    0
    Hi fellas,

    Great message boards here. I hope I can get some answers.

    On the back of my receiver, I see one optical jack for my cable receiver. Unfortunately, my cable box only takes Coax as its digital output. Does this make sense? I don't know why, but I also see Coax jacks on the back of my RECEIVER - I thought only optical could be used to transmit digital sound.

    So basically, I need to know a few things:

    Are Coax and Coaxial the same thing?
    Is there a way to easily convert coax -> optical and vice versa?
    If Coax and Coaxial aren't the same thing, can someone give me a link directing me to where I could find one? I tried some coaxial cables I had lying around and I thought it'd be rediculous that a coaxial would even FIT in a digital audio jack, and, not to my surprise, the Coaxial cable did not fit in any of the jacks.

    I know, this is a really stupid post, but I really don't have any other resources for knowing these things.

    If there isn't a way to easily convert these, should I just get a new DVD/SACD player? I am thinking about getting a 5-cd DVD/SACD changer that is on sale on Amazon.com - it is a Sony model, but I unfrotunately do not remember/know the model number.

    Thanks in advance!
     
  2. ChrisWiggles

    ChrisWiggles Producer

    Joined:
    Aug 19, 2002
    Messages:
    4,791
    Likes Received:
    1
    Trophy Points:
    0
    Coax is the same as coaxial, it's just short a few letters because people are lazy [​IMG]. Like me.

    Coaxial cable is used for a variety of applications, and is your standard cable. You'll find video, audio, cable TV, antennas stuff, all use coaxial cables of one kind or another often.

    When we're talking about digital audio transmission, the actual transmission method is called SPDIF, and can be transmitted via a 75ohm coax cable (you can buy them labeled 'digital coax' cables, or any good video cable will work, since video cables are 75ohm coax--the same thing), or can be transmitted via optical cables. (there is some other stuff done professionally, but is of no concern here.) The above are usually terminated in RCA plugs, or in the case of cable TV and antennas, in F-type screw plugs, or in the pro world often BNC connectors.

    There is no difference, IMO, though, though coax cable is cheaper so just run that. There isn't really any reason to run optical cables unless you've run out digital coax output/inputs, or that's the only plug available.

    Yes, radio shack sells dig. coax to optical and vice versa converters, but there is rarely a need for them except for simplicity in some cases. You don't look like you need one, you can just run coax no problem.

    FYI: If you are using a player with DVD-A or SACD capability, you *must* also use the analog outputs, using 6 runs of wire, or you won't get any high-res audio. The output from the digital out will not be high-res. It looks like you had a lot of questions in that post, and I could probably keep clarifying for a while, but see if that helps a little, and then come back with your next bout of questions and we can help with more specifics.

    [​IMG]
     
  3. Wayde_R

    Wayde_R Stunt Coordinator

    Joined:
    Aug 25, 2003
    Messages:
    244
    Likes Received:
    0
    Trophy Points:
    0
    Coax is abbreviation of Coaxial (it's kind of generic term for any cable with a positive pin and a shielded ground). Both RCA cables and cable TV coax fit the bill, as do old fashioned style LAN cables.

    Digital audio output is the S/PDIF format, and can be transmitted by either optical (toslink) or digital coax (basically 75ohm RCA cables).

    Your issue with the optical plug for you receiver's "Cable" in, and Coax output on your cable box is common. It makes perfect sense. Frankly it is the BANE of many an audio enthusiasts existence,[​IMG] Your not alone.



    DVD-A and SACD are great! Your receiver must have a 5.1 analog input to use those formats. So, make sure you have one of these on your receiver before making the plunge into the hi-res music formats.
     
  4. ChrisWiggles

    ChrisWiggles Producer

    Joined:
    Aug 19, 2002
    Messages:
    4,791
    Likes Received:
    1
    Trophy Points:
    0
    Wayde is right-on except for this part:


    Using a digital input for the CD player uses the DACs in the receiver, rather than the CD player. Depending on if you have a decent system or better, there will be differences with different DACs. Which one is better depends, you should listen both ways if that's an option (if you have digital outs on your CDP). On my system, indeed the DACs on my receiver are superior for my tastes. But there certainly is a difference in DACs, suggesting otherwise is misleading.
     
  5. Wayde_R

    Wayde_R Stunt Coordinator

    Joined:
    Aug 25, 2003
    Messages:
    244
    Likes Received:
    0
    Trophy Points:
    0
    You're right Chris.

    I didn't mean deceive. Personally, I think it's more important to have 5.1 sound off my cable box than use my receiver's dacs, my CD player's dacs will do just fine.

    But that's just me, based on the person's line of questioning I made the assumption he didn't care which dacs he used either.

    If it came down to having only Dolby Pro Logic on HBO movies or my CD players DACs, I'll take my CD player's dacs.

    I didn't meant to make that crack about the wooden knobs. I was just joking, I don't equate different DACs to audio voo-doo. However, think most people are using what they believe to be the "good" dacs when there isn't really much difference. I can only really speak for my own system.
     
  6. ChrisWiggles

    ChrisWiggles Producer

    Joined:
    Aug 19, 2002
    Messages:
    4,791
    Likes Received:
    1
    Trophy Points:
    0
    Mk, what stuck out was the wooden knobs comparison is all, which is certainly not the case.

    You're right if you only have one digital input, but I am certainly assuming that he has more than one, in which case he can use both at the same time (if the receiver is better DAC, which it may well not be), or even use a coax-optical converter if necessary. But I am assuming he has enough inputs.
     
  7. Wayde_R

    Wayde_R Stunt Coordinator

    Joined:
    Aug 25, 2003
    Messages:
    244
    Likes Received:
    0
    Trophy Points:
    0
    The wooden knobs are so funny[​IMG] I just have to reference them whenever I can.

    From now on in my own personal mythology "wooden knobs" are an analogy for many things. It'll take me awhile before I get it right.

    Well, another day, another set of wooden knobs. And if you believe that, I have some wooden knobs I want to sell you.

    Good night!

    Wayde
     
  8. ChrisWiggles

    ChrisWiggles Producer

    Joined:
    Aug 19, 2002
    Messages:
    4,791
    Likes Received:
    1
    Trophy Points:
    0
    There was an article I had a while back about fruit used in the same vein as the knobs. I think avacados worked better then lemons.... or something like that... [​IMG]
     
  9. Tim Hoover

    Tim Hoover Screenwriter

    Joined:
    May 27, 2001
    Messages:
    1,422
    Likes Received:
    0
    Trophy Points:
    0
    Lemons gave my rig a really bright sound...
     
  10. Andrew_G

    Andrew_G Agent

    Joined:
    Jul 10, 2004
    Messages:
    33
    Likes Received:
    0
    Trophy Points:
    0
    Well it appears that I probably should just stay away from digital audio for now [​IMG] It's kind of strange, however, that such a high-end manufacturer like Pioneer could skimp on something like this, though! [​IMG]

    Oh and actually I do care a lot about where my inputs are and how they are hooked up. Unfortunately, I am the only person that actually knows anything about ANYTHING in my family (well.. maybe not [​IMG]) but I am a headphone guy and my family has enough trouble getting those to work, I don't know if the speakers will be any easier - probably much harder. I'll just simulate the surround on all of our media but I'll get analog 5.1 for our DVD/SACD player because this will be primarily a DVD and Music setup anyway [​IMG]


    How do I, by chance, hook up analog 5.1? I have the left and right RCA plugs on my DVD/CD player right now and I can get simulated surround sound but not the real thing.

    Must my DVD player have it? And will my Pioneer 514K receiver have the correct inputs for it?

    Thanks a million guys! Lots of useful information here.
     

Share This Page