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Discussion Starter #1
Hey, a question:


Did N E body notice any difference between HDMI sound and digital coax/optical sound. From an HD player, i thought the sound should be uncompressed through HDMI. I had the digital coax setup, and after i changed to HDMI, there was no difference in the sound.

If thats the case with all of you , and there is no audible difference, why would N E body change over to HDMI> I think its overrated.

THnx
 

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There is always a subjective element when asking if they "notice any difference." Some say they notice a difference between the coax digital audio connection and the Toslink one. I for one cannot.


I find the only advantage of HDMI is there's just one cable for both audio and video.
 

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It has more to do with what sound source signal you are using. If the source is plain old DD or DTS, there should be no difference between transmission over HDMI or over S/PDIF. If the signal is of higher resolution and/or lossless, the differences may be apparent depending on the system and the individual listener.
 

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Quote:
Originally Posted by Kal Rubinson /forum/post/0


If the signal is of higher resolution and/or lossless, the differences may be apparent depending on the system and the individual listener.

That's an interesting point. I thought that digital coax and Toslink were error checking and HDMI only streams the data. If so, HDMI can lose bits while the other two would re-transmit providing better fidelity. I may be wrong.
 

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Quote:
Originally Posted by MTAtech /forum/post/0


That's an interesting point. I thought that digital coax and Toslink were error checking and HDMI only streams the data. If so, HDMI can lose bits while the other two would re-transmit providing better fidelity. I may be wrong.

I don't see the relevance of this issue to the question. It is not the transmission that is lossy but, rather, the sources.
 

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I think these type of questions will better be answered by this fall with all the newer AVRs coming...
 

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I went into some details regarding HDMI's error correction methods here:
http://www.avsforum.com/avs-vb/showt...post10603513


In summary, our method is to apply an encoding algorithm that will prevent errors from occurring in the first place. We applying something called TERC4 to turn ever 4bits of audio data into a 10bit word. This method gives the audio data more "strength" or "robustness" form a digital perspective. In addition, we also use the industry established ECC (Error Correction Code) parity for the data islands packets (which contains the audio and control data). You can see here that these encoding method took careful consideration into giving higher amounts of error correction to data that is most critical and noticeable (control signals and audio).


From a quality perspective, the key is not the audio data errors (believe me, if there was an error, you would hear it quite clearly as a pop or other obvious artifact). The key is the quality of the PLL in the receiver chip, which determines the jitter & signal to noise ratio when it get ultimately fed into the amp.


Think of HDMI as a data pipe that gets the data quite exactly from one end to the other. So HDMI does not inherently bring better quality vs. SPDIF. That quality is dictated by the other performance qualities of the components.
 

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Also keep in mind that HDMI can transmit the same digital bitstreams that SPDIF sends, like Dolby Digital & DTS. So think of HDMI as just a different physical medium for transporting those audio formats. Not really any better or worse, just different.
 

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Discussion Starter #10
Thank You for all your replies.


I guess i will just stick with the digital coax since its the same (no audible difference) quality until HDMI fixes all the bugs. WHEWWW, i dont have to run out and get HDMI components just yet. I'll wait until the audio/video HDMI (since not all of them do it yet) comes out.


THNX
 
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