[dts_boy]

i have an onkyo 905 amp and a 504 dvd player and currently connected via hdmi. my question is this - is the hdmi connection better than digital coax for audio or should i hook the coax up and enjoy better sound (hopefully?)
i guess this might open a can of worms but a recent cable tidy up means i now have a spare chord prodac pro lying around

[Slimbert]

Thanks for starting this thread as i've wondered which people prefer!

If you decide to get rid of the prodac i'll take it as ive always regreted getting rid of mine!

[Neil Hawkes]

In much the same vein, has anyone experienced any difference in optical over coax?

Cheers,
Neil.

[MI55ION]

For HD content I use HDMI and coax for everything else. Perhaps it's a combination of my room, my kit and my ears but I find the difference virtually non existent to subtle at most.

[MI55ION]

Originally Posted by Neil Hawkes

In much the same vein, has anyone experienced any difference in optical over coax?

Cheers,
Neil.

Arcam recommends coax over optical every time, they probably have their reasons.

[Neil Hawkes]

Originally Posted by MI55ION

Arcam recommends coax over optical every time, they probably have their reasons.

Thanks Mission,
I'd better get me one then!

Cheers,
Neil.

[RooDBwoY]

It's logical to suggest that coaxial is a truer representation of the signal being read because:

With coaxial the data is read optically from a disc, which is then sent through the insides of the machine electrically and eventually gets spit out the back of the machine STILL electrically.

With optical the data is read optically from a disc, which is then sent through the insides of the machine electrically, then gets converted from electrical to optical, then spit out of the machine.

With electrical (coaxial) there is one less conversion process.

[dts_boy]

Hmmm, its all very interesting but still no real answer! i guess i need to try it and see for myself i guess. its interesting as i even called the manufacturer to ask and they referred me to the manual - how helpful

[Slimbert]

I definately prefer Coax to Optical, no idea why it's just the way i've always liked it, but i've never heard HMDI audio except straight into my tele which has rubbish speakers.

I seem to remember hearing somewhere that HDMI audio is totally uncompressed so it's a more natural sound but I can't think where I heard it!

People do seem to be going a bit loopy over HDMI receivers but i'd have to spend a small fortune to get a THX amp like mine with HDMI so I think i'll stick with the one I have for a while longer!

[paulrandom]

DEFINETELY hdmi, no question.
HDMI has HUGE bandwidth (36.86Mbit/s dedicated for audio) compared to S/PDIF, which only has about 1Mbit/s.

Furthermore, HDMI supports (can transmit) almost any encoding (Dolby TrueHD, DTS-HD, uncompressed etc.), sampling rate (even 192kHz), bit depth and number of channels on the market;
while S/PDIF is limited to only Dolby Digital (AC3, which is limited to 48kHz, 5.1 channels and 640kbit/s) or DTS audio (which is also limited by S/PDIF bandwidth, hence no 96kHz 24bit 7.1 channel DTS audio over S/PDIF ).

As for optical/coax, I REALLY doubt there can be a difference, as the signal is digital, much like in HDMI, so it is not affected by the cable/connection quality (unless it is too bad to transmit a signal). It either works or it doesn't. Correct me if I'm wrong.

Hope this helps.

P.S. first post, hi everyone!

[farmerpalmer]

Originally Posted by RooDBwoY

It's logical to suggest that coaxial is a truer representation of the signal being read because:

With coaxial the data is read optically from a disc, which is then sent through the insides of the machine electrically and eventually gets spit out the back of the machine STILL electrically.

With optical the data is read optically from a disc, which is then sent through the insides of the machine electrically, then gets converted from electrical to optical, then spit out of the machine.

With electrical (coaxial) there is one less conversion process.

actually there are two - the source has to convert electrical to optical (as you said), but also the receiver has to convert optical back to electrical, whereas coax removes these two conversions.

[morksbeanbag]

Originally Posted by RooDBwoY

It's logical to suggest that coaxial is a truer representation of the signal being read because:

With coaxial the data is read optically from a disc, which is then sent through the insides of the machine electrically and eventually gets spit out the back of the machine STILL electrically.

With optical the data is read optically from a disc, which is then sent through the insides of the machine electrically, then gets converted from electrical to optical, then spit out of the machine.

With electrical (coaxial) there is one less conversion process.

Two less actually. Signals across optical go from electrical to light, and then from light back to electrical. All this is done via the little black rectangle input blocks, thats the only part that does the conversions and is therefore as important if not more so than the cable that links them. It's interesting to note that on Sony's highest end 9000ES kit of seperates on their dvd player and the dvd input on the processor they used optical input blocks of double the size (a higher quality unit) normally found on AV kit.

I'd still use coax over optical but with the advent of the new HD codecs both of these connections will probably go the way of the dinosaur in AV kit in the next few years.

Just been reading that optical and coaxial outputs are capable of transmission speeds up to 13mb per second! Though even 24/96 outputs for dvd are only 4.6mb per second.