Fiber optics and Bluray

[jjc]

I have a Panasonic Bluray that has a digital fiber optic output for audio. Does anyone know if

I use this connection does it output the same uncompressed signal to the preamp for audio, or

is the HDMI the only output that sends all the 7.1 audio info forward. Thanks Jim

[JohnA]

My Sony BluRay player will send Dolby Digital, DD EX (7.1), DTS and DTS ES (7.1), plus 44.1 kHz PCM from CDs to my Pre-Pro via a coaxial RCA cable or a Toslink optical cable.

The high end formats like Dolby True-HD and DTS-HD comes out via the HDMI.

Optical cables cannot contribute to ground loop hums, but add another pair of conversions (electrical to light and back). So I use the coaxial analog outs when I can.

[jjc]

Thanks for the reply. You use you`re coax, do you do this rather than using fiber optics? I have

both coax and fiber optics and never have used coax. I there a advantage to the coax?

[JohnA]

They do not "add another pair of conversions (electrical to light and back)." That could result in fewer errors in the Digital-to-Analog process.

[wuzzzer]

http://stereos.about.com/od/accessoriesheadphones/a/digaudiocables.htm

[oldtimer]

use either coax or fiber optic, it's one or the other and it really doesn't matter which, unless you have a run with sharp bends, then do not use optical. As above the newest formats are through the hdmi out. My question is in that case your pre/pro would also have to have the capability to decode the newer formats right? Otherwise use the analog multi-channel outs?

[BE36]

Many good comments about HDMI & Fiber Optic Cables.

I had a system with HDMI / BluRay and both the Pre-amp & Player were able to decode True-HD & DTS HD.

I switched to older, higher quality pre-amp and Fiber Connection with out the ability to decode True-HD & DTS HD and performance actually improved:

1) Better preamp much more realistic sound and more detail.

2) Studio Bit rates are limited - Not many BluRays are recorded at Sampling & Bit Rates any higher than at what DVD's are/can be recorded.

3) Law of deminishing returns - After 48 KHz by 24 Bits my Ear can not really hear any improvements at higher Sampling Rates. When I had the HD Pre-amp even the super Sampling & Bit rates recodings, Chris Botti 96 KHz & 24Bits did not sound different then when that same disk was played at 48 Khz & 24 Bits.

4) Well recorded & Mixed DVDs when press at recorded at higher Sampling & Bit Rates, 48 KHz X 24 Bits, Dave Matthews & Tim Reynolds at Radio City for example, sound better than 96 KHz & 24 Bits that was not well recorded and mixed.

I still like the migration to BluRay since the ability to store more data encourages the use of atleast 48Khz X 24 Bits while still being able to include other tracks, Spanish, French, etc.

Off note all these bit rates are higher that was is avilible to the Movie Theaters on film. The reason sound is good at the Theater - Room size, Biamping, Good equipement, preamps, amps etc. managing room reflections, speaker placement etc.

Link to info on Bit Rates:

http://en.wikipedia.org/wiki/DTS_(sound_system)

There may be some Audiophiles that can hear the the differane between 48 & 96 Khz at 24 bits, until I get equipement with higer quality DACs, I can not.

What I can hear is the difference between:

CDs at 44.1 KHz & 16 bits versus 48 Khz & 24 bits of DVDs & BluRay.

Well recorded, mixed and pressed DVDs & BluRays versues not so well done DVDs & BluRays.

Good equipment and room acoustics.

So in summary just because there is a lot of data availible from the equipment/cable the room, DACs, Pre-amp, Amp and the Studio have to be able to take advantage of it or it is just cancelled out by the weakest link in the chain.

[cyberimage]

YOU NEVER WANT TO USE OPTICAL for SOUND on BLU_RAY PERIOD

the TOS OPTICAL cables are limited in bandwidth to 1.2-1.5 MbPS throughput

so that means they will NOT do DD 7.1 HD or DTS HD properly as those require much higher bandwidth of like

5-15 MbPS

use HDMI its a much higher bandwidth cable 10-15 MbPS and thus will give you the HD sound

or uncompressed LPCM whihc can be 14 channels and 18 MbPS

TOS fiber optic cables start to make errors at over 1.2 MbPS and have to be converted which is another disadvantage

HDMI is the logical choice

[wuzzzer]

YOU NEVER WANT TO USE OPTICAL for SOUND on BLU_RAY PERIOD

Unless, of course, you only have optical inputs for audio on a receiver/pre-amp.

[cyberimage]

No you still dont

if you dont have HDMI then you merely get a converter box that has a buffer so it can take the optical data --store a few seconds of it at a time and then converts it to HDMI, IE optical to HDMI, they are around..

[psg]

Many good comments about HDMI & Fiber Optic Cables.

I had a system with HDMI / BluRay and both the Pre-amp & Player were able to decode True-HD & DTS HD.

I switched to older, higher quality pre-amp and Fiber Connection with out the ability to decode True-HD & DTS HD and performance actually improved:

Surprising because I find a huge difference between most DVDs and Blu Ray. I attribute it perhaps not to the better lossless codecs, but rather to the producers actually using the codecs to put more dynamic recordings on them. You mention Dave Matthews & Tim Reynolds. It sounds fantastic on Blu Ray.

[jjc]

Thanks guys for all the help but I finally gave in and purchased

a new Rotel Home Theater receiver and I love it. I still like my old

Pro logic system with seperate amps but I have to say this Rotel

is sweet sounding and everything just plugs in and I still can plug in some

outragious amps to the front 3 channels, its a high quality

piece. Now on to the rest of the system thats the speakers and

I`m looking to put some Klipschs together and I`ll bet this is the

place to be for that. Thanks Jim

[wuzzzer]

No you still dont

if you dont have HDMI then you merely get a converter box that has a buffer so it can take the optical data --store a few seconds of it at a time and then converts it to HDMI, IE optical to HDMI, they are around..

I don't see how someone who doesn't have any kind of HDMI connection in their audio equipment would benefit from an optical to HDMI convertor box. Take the optical signal, convert it to HDMI, then do what with it?

If someone has ONLY optical/coaxial inputs but not HDMI inputs in their receiver or pre-amp the connection of audio-in will have to be toslink/coaxial. Even if there were devices to do the opposite as you suggested (which would be take HDMI and convert it to optical/coaxial) the limitations of what can be carried via optical/coaxial cable would negate any benefits of doing so.

Someone correct me if I'm wrong.

{edit} Obviously 5.1 or 7.1 discrete outputs from Blu-Ray source to receiver/pre-amp would allow HD audio, I'm just talking digital here.

[BE36]

Maybe I should try a convertor Box with Dave & Tim on BluRay and get the best of both worlds?

Any recomendation on a brand?

[BE36]

What if all you have is 5.1 and only are only really critcal of the sound when listening to the BluRay Player out puting Stereo?

[cyberimage]

well just cause you dont see does not mean itws not true

the primary disadvantage of optical is throughtput

which is limited to about 1.5 gps

if you use a converter,, it fools the DVD player into thinking you have HDMI and outputs

HD audio at full HD audio 7.1 bitstream

normally this would be a problem for the receiver that has the optical going into it,

but since the converter box has ram as a buffer it allows and compensated for the higher throughput by buffering the data

in memory to allow for the reduced throughput,, using a buffer , this is what computers do all the time and EThernet does as well

as video,, so this is just dong it with sound..

soundblasters cards and other computer sound cards do this all the time

get it now?

[BE36]

Even though I am Mechanical Engineer I got some of it.

HDMI connection would still be better? No Buffering?

Do you recommend a Brand that is higher quality?

If you come by Detroit we can have a few Daddy Pops and you can hear an Elite with HDMI vs. McIntosh with Fiber on 2 Channel.

[BE36]

I do not have an HDMI on my Processor.

Based on recommendations on this tread:

Switched from Optical to Anolg outs on the Pioneer BDP-05.

For 5.1:

Seems to have improved the sound since taking advantage of the HD track on National Treasure 2 with out all the Jitter?, noticed birds chirping in the Buckingham Palace scene and when the bee appeared at Mt. Rushmore I was looking away from the screen and thought there was actually a Bee in the house.

Initial I thought it better to use the optical and let the McIntosh with it's better 24 Bit DACs? to do the Digital to Analog conversion versus the Pioneer with Wolson 8740s doing 2 channels each. Bad assumption?

For Stereo:

Did not hear a huge difference most likely Jitter with only two channels over the Fiber is not significanly going over 1.5 Mps? Or a little of the Better DACs on the McIntosh? I do not know what the Mc uses for DACs Does anybody out there know?

I would like to get the DACs replaced in the Pioneer or try a new Player with better & more DAC to see if there is much of an improvement.

Does anyone know someone who replaces DACs on BluRay's, Upgrade Caps on Blu-Rays?

[Rich_Guy]

Something not mentioned here is if you cannot use hdmi for sound
then the next best is to use analog 7.1 audio connectors if possible.

Also Blu-ray video will look best over HDMI or DVI cable. Avoid analog video cables (component, S-video, composite,etc.) with a blu-ray player as a blu-ray cannot upscale with these connectors giving HDMI and DVI a big advantage. However component cable is great for HD cable boxes, DVRs, etc, giving as good a picture quality as hdmi or DVI without having to make a "digital handshake" which can slow down tuners considerably.

[BE36]

Rich Guy you are right on.

Switched to the Analog outs and with out the gitter got much better results with 5.1 surround utilizing Master and True, on stereo did not notice much of a change if anything versus fiber.

To me the big change in quality comes from Redbook CD at 44 Khz and 16 bits to 48 Khz and 24 bits DVD/Bluray etc.

When I go up to 96Khz and 24 bits I do not here the differance - thinking that my DACs are not up to the challenge or my hearing is not up to the challenge?