Tv programs in 5.1 sound

[marty 17]

Just wondering if any HD channels use 5.1 sound please as I have a new Amplifier I wish to try with my sat receiver and also is HDMI or Optical/Coax best to use.

[mandc]

Today channel 73..7mate...is transmitting Bathurst in HD and my amp is showing Dolby Digital on the amp (5.1) although at the moment the surround is only average.

I use optical out as my TV only has optical out (no coax digital). Make sure your amp will accept digital signals from HDMI before using that amp input. My amp...a cheap Yamaha RXV-385 has HDMI in but it is merely a video switch...It does not decode the digital sound from HDMI

Edit: Sorry, I just saw you were referring to satellite..Gem on D1 transmits in dolby digital but is currently showing a really old movie that obviously is not in 5.1...I don't have Austar in HD so don't know about them

[mborkp]

Fox has few movie channels in 5.1. I think, even few in SD are 5.1. You might need to select DD on your receiver. My oryginal HD receiver is dusting the shelf since when I got it, (using 3rd party with "blue") and I can't remember if the provider's receiver sends 5.1 via HDMI. Use HDMI if possible to reduce the cables, but if not then Optical, same quality.

Cheers

[Drift]

I know this is going to open a can of worms, however the best sound quality will come via HDMI or coax. The difference is noticeable even with average equipment these days.

Having said that, your source is going to be the biggest issue. A heavily compressed or low quality source isn't going to sound any better no matter what quality the connection.

[mborkp]

I think, optical was designed to handle up to 7.1 audio compression. HDMI was designed to handle bitstreaming (uncompressed audio). I can't see why HDMI is better for DD5.1 as optical handle 5.1 bitrate easy?

Cheers

[Drift]

Optical may well be able to handle 7.1 in theory, although I don't think there are any consumer goods that support DTS-HD & DDTHD via TOSLINK.

Perhaps it's just me being particularly pedantic about sound quality (which admittedly, I am), and to most the difference would be negligible. I recall having a similar discussion with a fellow 10 years ago before I was a believer in coax. He was installing home theaters at the time and explained that he never used optical due to the sound quality. I didn't believe that there'd be such a difference until I tried it.

Although the specifications for S/PDIF Coax via RCA & TOSLINK are the same, I've always found much better sound quality from coax. Less attenuation of high frequency sounds and much warmer mids & lows. This has carried across various systems and components over the past 10 years. Now I've gone to HDMI, I only use S/PDIF for legacy devices.

[mborkp]

"... Bit rate or amount is determined by the processor, the integrated circuit that is responsible for the digital signal output. A coaxial or optical is used for 24 bit 96khz or 192khz audio, so it in effect would be quite capable of handling the output of a dvd audio processor output which is up to 24 bit 192khz. ...

E. Ramsey AAS industrial electronics"

Cheers

[mborkp]

ahhh... the Fox is a standart DD2.0, DD2.1 or sometime DD5.1
Sure, Optical/Coax is not good for HD Audio (bitstreaming) but this formats are not seen in sat transmission (at least on fox)

Cheers

[mborkp]

and this is interesting:
"When correctly connected, Coax and Optical should be exactly the same. Bandwidth isn't and issue, error correction (when connected correctly) isn't and issue. Distance, say over 50 feet might lean toward optical but who does that? Optical cables can be miles long compared to copper's hundreds of feet for the same amount of signal loss. Optical cable can be fragile and cannot be taken around corners too tightly or pinched. For all intents and purposes though, it doesn't make a difference which one you use.

Now, having said that, there are a couple of situation where one MIGHT be better than the other. They both fall under "defective equipment" though.

1. The CD data, though optical, is converted to a electrical signal. To create an optical signal, this elctrical signal - essentially the coax signal, has to be convered to optical by a laser-diode. You could theorize that am optical signal could not be superior to a coax signal because it is derived from the coax signal. I would not worry about it though.

2. Optical connections do not carry grounds. In a pooly designed system an optical connection COULD produce less hum because there are fewer ground paths. The music to the decoder would not be any better but a crappy amp could add hum to an otherwise pristine music signal just before it got to the speakers. This hum would be faily obvious though.

Again, if you have good equipment, use either one. "

all the info from:

Cheers

[Drift]

I appreciate that in a perfect world, there should be no difference. Unfortunately we don't live in a perfect world and the vast majority of us don't have 10s of thousands to splash on a high end sound system, thus we're relegated to consumer products that are often less than perfect. All the theory in the world wont change the what you hear.

This is a similar argument to that of requiring a specific value resistor to run an LED from a given voltage. For instance with a typical red LED (Vf 2V, If 20mA) run from 12V, theory tells us we require a 560Ω resistor. The truth of the matter is it'll run just fine (albeit with a barely noticeable change in intensity) with a 1k or 3k3. We can see that, and don't require theory to tell us any different.