View Full Version : Need some clarification on HDMI and it passing digital audio…


Matt_Smi
12-29-07, 08:48 PM
So I suppose this is rookie question to the max, but I just ordered an Onkyo 805 to go with my new Ascend speakers (170 SE’s, soon to be Sierra’s across the front, and making the 170s my surrounds). Anyway I plan to hook all my sources into the 805 and run one HDMI cable out back into my TV, this should keep things easy and also keep my cables clean. For my HD box and X-Box 360, I will hook them up via HDMI, so from my understanding HDMI will pass digital audio right? So there will be no need to also run optical or coax cables from these sources into my AVR in order to get DD/DTS sound correct?

I was wondering why high end receivers were starting to have less digital inputs (805 has three optical and 3 coax, two years ago a receiver this price would have like five optical’s), but if HDMI passes digital audio as well then I guess it makes sense. This would be good because I would like to use the two optical inputs for my older DVD player (no HDMI output, not upgrading until I get a new TV) and the other one for either PS2 or CD player.

So I guess the underlying question here is will any source pass digital audio as well as video though the HDMI cable, or does it need to support a special revision (like 1.3a) or some crap like that. My X-box and HD Box are both brand new and it would be sweet to just run HDMI cables from them and free up my optical inputs for other sources, which I suppose is one of the big selling points for HDMI, but like I said I am just not sure if mostly all devices support streaming digital audio though HDMI. Thanks for the clarification on this.

KurtBJC
12-29-07, 11:07 PM
Yes, any source that's HDMI-compliant is going to send audio along with video; and this is true regardless of HDMI spec version (e.g., 1.2, 1.3, etc.).

Kurt
Blue Jeans Cable

Matt_Smi
12-30-07, 12:32 AM
Yes, any source that's HDMI-compliant is going to send audio along with video; and this is true regardless of HDMI spec version (e.g., 1.2, 1.3, etc.).

Kurt
Blue Jeans Cable

Great, now are there any exceptions to this rule? IE audio not passing as it should, or not getting DD/DTS out of the source? But rather just a regular signal, I would assume not since HDMI is all digital but I am really not too sure. Thanks for your response!

KurtBJC
12-30-07, 12:05 PM
Not often. There are occasional HDMI "handshake" issues, and it's possible for the sending device not to "know" that the receiving device accepts audio, but those sorts of malfunctions are quite rare, so I really wouldn't worry about that unless and until it comes up. If things are working correctly--which they do in the great majority of cases--you shouldn't have any problems with getting audio to run.

Kurt
Blue Jeans Cable

meaton
12-30-07, 01:39 PM
Kurt,
I received a Toshiba HD-A3 player for Xmas. Should I buy an HDMI cable to connect to a Samsung 56" DLP TV. The Samsung has the HDMI port as well as the "RCA Jacks". I have already connected using the red-white-yellow cables and it plays just fine. My questions are:
- Will an HDMI cable make a significant diference in Picture or sound quality?
- I would only need a 4-5 foot cable, what brand do you recommend?
- I looked at cables at Best Buy and they had Monster 1000, 800, 600 & 400... What is the diference and is my TV or the A-3 capable of the higher "speeds" of the more expensive cables? i.e. is it a waste of money to buy a very expensive cable versus an inexpensive (slow) cable?
Thanks for your help...Mark

KurtBJC
12-30-07, 03:01 PM
The red/white/yellow is composite video with stereo analog audio, is limited to standard-definition 480i, and provides lousy color definition. You'd get a significantly better picture using either component video (red/green/blue for the video, plus another cable for whatever type of audio hookup is available) or HDMI.

As for cable brand...well, I have a bias here since I sell 'em. But at four to five feet, the choice of cable is not going to make a difference to image quality, so my inclination would be to find something cheap. On our site, we have the Tartan 28 AWG (about four bucks for a six-footer), or if you prefer something which is primarily American-made, we also have the BJC Belden Series-F.

The cable "speed-rating" thing is, as used on retail packaging, a marketing gimmick. Mind you, there is such a thing as a cable not being up to the required bitrate, so the concept of speed-rating isn't nonsense, but the way it's being sold IS nonsense. We have an article about this on our site at: http://www.bluejeanscable.com/articles/speed-rated-hdmi-cables.htm

So the short answer to that speed question is: yes, your player is up to those higher speeds (not sure on the particular player, but if it's all 8-bit color and 1080p/60, your max speed would be 1.485 Gbps/channel, or 4.45 Gbps combined). But you do not need a special cable for that because at such a short distance, any cable you are likely to find will work equally well at these speeds.

Kurt
Blue Jeans Cable

webbah
01-01-08, 04:08 PM
So - I bought the Onkyo HT-SR800 and have my dvd player going to the receiver with both HDMI and optical for the audio. Then one HDMI to the TV. Question is - do I need the optical from my DVD to the receiver?

ccotenj
01-01-08, 06:08 PM
So - I bought the Onkyo HT-SR800 and have my dvd player going to the receiver with both HDMI and optical for the audio. Then one HDMI to the TV. Question is - do I need the optical from my DVD to the receiver?

does the avr process pcm over hdmi? if so, then you don't need the optical.

easy to test this. unplug the optical and assign the source to hdmi and see what happens.