Will the PS3 ever do 7.1 via the optical cable? Doesn't the 360 do that? My receiver does 7.1 but it only does it via optical not HDMI.

I think TOSLink might not provide enough bandwidth to do over 5.1 Bitstream and 2 channel PCM. I might be wrong though.

It's not a limitation of the Playstation, it's a the fiber optic cable. PS3 can output 7.1 discrete audio channels, over TOSlink, in Dolby Digital and DTS. Optical can also pass 2 channel uncompressed PCM.

Optical will never be able to carry 7.1 (or even 5.1) channels for PCM, Dolby True HD, or DTS-HD.

If your receiver has an HDMI input and output and does processes through these inputs (isn't just a passthrough), than it should pass 7.1 tracks. What kind of receiver?

Dolby Digital and DTS do not support 7.1. They support a maximum of 6.1.

Fiber optic technology is not the limiting factor. It is the implementation of that technology in CE devices that limits Dolby Digital to 640Kbps, DTS to 1.5Mbps, and LPCM to stereo.

It's not a limitation of the Playstation, it's a the fiber optic cable. PS3 can output 7.1 discrete audio channels, over TOSlink, in Dolby Digital and DTS. Optical can also pass 2 channel uncompressed PCM.

Optical will never be able to carry 7.1 (or even 5.1) channels for PCM, Dolby True HD, or DTS-HD.

If your receiver has an HDMI input and output and does processes through these inputs (isn't just a passthrough), than it should pass 7.1 tracks. What kind of receiver?

Pioneer VSX1016.

So how should I set the audio options, do I say bitstream or linear if I connect it via Optical?

So how should I set the audio options, do I say bitstream or linear if I connect it via Optical?Bitstream.

When playing movies, select Dolby Digital and DTS, not LPCM. If the choices are between TrueHD and LPCM, choose TrueHD, as selecting that track will output the backward-compatible Dolby Digital track through optical/coax on most players.

It's not a limitation of the Playstation, it's a the fiber optic cable. PS3 can output 7.1 discrete audio channels, over TOSlink, in Dolby Digital and DTS. Optical can also pass 2 channel uncompressed PCM.

Optical will never be able to carry 7.1 (or even 5.1) channels for PCM, Dolby True HD, or DTS-HD.

If your receiver has an HDMI input and output and does processes through these inputs (isn't just a passthrough), than it should pass 7.1 tracks. What kind of receiver?

Technically it's not the cable that is the bottleneck. It is the Toslink protocol and the hardware converters in the PS3 and the AVR (Electrical to light then back to Electrical again) That wont allow the bandwidth for LPCM via optical.

Just set the output to Bitstream and let the PS3 send the audio track in that format and allow the AVR to decoded it and process it into 5.1 or 7.1

Technically it's not the cable that is the bottleneck. It is the Toslink protocol and the hardware converters in the PS3 and the AVR (Electrical to light then back to Electrical again) That wont allow the bandwidth for LPCM via optical.

Just set the output to Bitstream and let the PS3 send the audio track in that format and allow the AVR to decoded it and process it into 5.1 or 7.1

Interesting discussion guys.

I have an Alesis ADAT machine used in my home studio. They have their own fiber optic connection (Toslink) that passes 8 uncompressed audio channels at once. This is older tech, been around since the late Eighties. The bandwidth is there, I would think through a firmware upgrade, the same could be accomplished on a PS3. The ADAT standard was 24/48, but again, a limitation of old hardware, I believe the optical cable is capable of 24/96, maybe more.

In fact, since I'm on a budget with the home studio, I don't yet have a good set of studio monitors, so I'm using the PS3 to stream different mixes of a song to my Polk LSi 9's in the living room, with great results. I can preview without burning to a disk.

Optical has an insane amount of bandwidth. The problem is the cost of the equipment to the do conversion. We have optical cables here at work that are no thicker than Toslink cables, that carry OC-12 and OC-48's. OC-48 = 48 DS3's or 1344 T-1's Thats a lot of bandwidth in a single cable. So it isnt that optical cant support 8channels of audio (heck it could even do video) it's just the Hardware to support that isnt cheap. I think that is the main reason for HDMI. there is no Elec to Optical conversion..ie..cheaper cost, and Security can be implemented on HDMI easier since there is no conversion going on either....

Dolby Digital and DTS do not support 7.1. They support a maximum of 6.1.
Right, I was referring generically to their ES & EX counterparts, which use matrixing to achieve the 6th and 7th channels. I was wrong in saying "discrete channels."

I was just browsing through the digikey catalog and took a look at toslink transmitters. Most of them spec at about 13mbps or so. I don't know if some of the cheap cables would work very well at that kind of speed, but who knows. I highly doubt we will see an update to spdif anytime soon with hdmi hitting hard, so its really a non issue.

-Sean

Right, I was referring generically to their ES & EX counterparts, which use matrixing to achieve the 6th and 7th channels. I was wrong in saying "discrete channels."

even in that case it's still done by the receiver after the 6.1 signal is passed to the receiver. i dont think DD and DTS, EX/ES or not, go up to 7.1. They have 6.1 in either discrete or matrixed formats.

Technically it's not the cable that is the bottleneck. It is the Toslink protocol and the hardware converters in the PS3 and the AVR (Electrical to light then back to Electrical again) That wont allow the bandwidth for LPCM via optical.
Correct. I should have worded that differently!

I was just browsing through the digikey catalog and took a look at toslink transmitters. Most of them spec at about 13mbps or so. I don't know if some of the cheap cables would work very well at that kind of speed, but who knows. I highly doubt we will see an update to spdif anytime soon with hdmi hitting hard, so its really a non issue.

-Sean
I agree with you on the HDMI issue. Cheap cables or not isnt much of an issue so long as it's glass it really doesnt have much loss associated with them, and so long as the ends (connectors) are clean Optical can go great distances (compared to copper) with very lil loss of the signal. On the Toslink transmitters, to get more bandwidth out them would take more than firmware update. Just like with Bluray vs SD-DVD all they really did was change the wave length of the laser (red to blue) Same applies to optical. The wave length would need to be changed in order to get more bandwidth out them..this doesnt mean a new laser per se, but the at the very least a new oscillator (hardware) $$ would be needed. Nah... I see Toslink going the way of the Dodo bird.

Thanks everyone, excellent information, much appreciated!!!

Advanced receivers can matrix a 5.1 (or 6.1) DD or DTS track into 7.1 channels, using Dolby Pro Logic IIx or THX surround processing.

Otherwise Optical is limited to 6.1 (DD-EX, DTS-ES Matrix or Discrete).

I agree with you on the HDMI issue. Cheap cables or not isnt much of an issue so long as it's glass it really doesnt have much loss associated with them, and so long as the ends (connectors) are clean Optical can go great distances (compared to copper) with very lil loss of the signal. On the Toslink transmitters, to get more bandwidth out them would take more than firmware update. Just like with Bluray vs SD-DVD all they really did was change the wave length of the laser (red to blue) Same applies to optical. The wave length would need to be changed in order to get more bandwidth out them..this doesnt mean a new laser per se, but the at the very least a new oscillator (hardware) $$ would be needed. Nah... I see Toslink going the way of the Dodo bird.

Plus, even if they could do it with just a firmware update, they wouldn't because it lacks the copy protection of HDMI.

I believe it's the SPDIF standard that limits the bandwidth over optical. The specification says that so much bandwidth is needed, so then all Consumer Electronic companies build the hardware to meet the specs. They would have no need to build extra fast optical hardware because that's not what the specification requires. A whole new Toslink v2.0 could have allowed anything, but they went HDMI instead. Bottom line is that no SPDIF optical connection will support whole new bandwidth requirements...

AIUI the limitation for consumer optical and coax digital connections is a legacy of their original usage - 44.1KHz 16 bit stereo 2.0 PCM - as that is all that the original CD players output. When DAT came along 48KHz sampling was added - but that is about it.

The upper limit of the protocols used by CE gear is thus around 1.5Mbs - the bitrate for an uncompressed 2.0 16 bit stereo signal at 48KHz?

When DD and DTS were introduced as digital bitstreams carried via Toslink/SPDIF when DVD Players arrived they simply fitted their transport streams into these bandwiths - and again were limited by the 1.5Mbs ceiling?