A few ???'s for the pros

[CasualKiller]

Read in another thread that there's like a "ladder" of performance for inputs going from rca cables on the low to optical to digital coax, multi channel analog then finally HDMI being tops.

For this, what exactly are the bandwidth limitations of each, IE optical 1.5 Mbps etc.


Was also talking to a friend of mine about my new 7.1 audio set up, it's his opinion that such set ups are a marketing gimmick in being that all they do is split the rear channels of 5.1.

If this is true, some of my Blus have 7.1 Dolby and 6.1 Dolby , what exactly do audio formats like this do?

I use my PS3 for my Blu / cd / game system and run it to my STR-DG910, after reading around about LPCM and Bitstream I went out and purchased an HDMI cable and ran LPCM.

Am I correct to assume that the higher bit rates from lossless audio etc actually bring with them more sound adding a higher level of depth and range to the audio or is it somewhat of a "placebo" effect?

Really appreciate any help I can get, tried Google but its hard to get straight answers.

Thanks!

[Zaphod]

Originally Posted by CasualKiller

For this, what exactly are the bandwidth limitations of each, IE optical 1.5 Mbps etc.

I think you are confusing the bandwidth of a particular codec, versus the bandwidth of the connection.

For example, the optical (TOSLINK) specification has a "bandwidth" up to 125 Mbps (the original spec was around 3 Mbps) and HDMI up to 10.2 Gbps.

Do you meen specific codecs or the connection itself?

Also I'm assuming you mean the connections for CE's. There are different versions of TOSLINK that offer the higher bandwidth that are not found in CE's.

Also bandwidth is usually described in MHz or GHz as opposed to Mbps or Gbps.

[CasualKiller]

I think I did get confused, this is what I read in another thread:

Before I go any further, I would like to note that Optical and Digital Coaxial cables are insufficient and will only transmit 2.0 PCM audio. In other words, only stereo...they are not capable of delivering Lossless 5.1 or 7.1 surround sound.

https://forum.blu-ray.com/showthread.php?t=40821

I had assumed that this was due to bandwidth limitations, why then would optical not be able to carry these signals?

[richteer]

Originally Posted by CasualKiller

Was also talking to a friend of mine about my new 7.1 audio set up, it's his opinion that such set ups are a marketing gimmick in being that all they do is split the rear channels of 5.1.

If this is true, some of my Blus have 7.1 Dolby and 6.1 Dolby , what exactly do audio formats like this do?

Your friend is wrong. 7.1 is 7 true channels (plus the sub). Naturally, you'll need a 7.1 source to get the full effect of a 7.1 setup.

It is true that some 7.1 receivers have the facility to convert a 5.1 input to a pseudo 7.1 output. That might be where your friend is getting confused.

[Lucy Diamond]

Originally Posted by richteer

Your friend is wrong. 7.1 is 7 true channels (plus the sub). Naturally, you'll need a 7.1 source to get the full effect of a 7.1 setup.

It is true that some 7.1 receivers have the facility to convert a 5.1 input to a pseudo 7.1 output. That might be where your friend is getting confused.

Well said. I would like to add that exactly how "7.1" your mix is depends on the mastering.

Some people master both the surround backs as a single center channel, which tends to be the norm, BUT the ability to pan between them is there. It all depends on how the source is engineered.

When you find a totally tricked 7.1 master though...the imaging is beyond sick to the point where you will find yourself looking over your shoulder.

This is definitely an exciting time for home theater people.

Later all.

[Big Daddy]

Originally Posted by CasualKiller

Read in another thread that there's like a "ladder" of performance for inputs going from rca cables on the low to optical to digital coax, multi channel analog then finally HDMI being tops.

For this, what exactly are the bandwidth limitations of each, IE optical 1.5 Mbps etc.


Was also talking to a friend of mine about my new 7.1 audio set up, it's his opinion that such set ups are a marketing gimmick in being that all they do is split the rear channels of 5.1.

If this is true, some of my Blus have 7.1 Dolby and 6.1 Dolby , what exactly do audio formats like this do?

I use my PS3 for my Blu / cd / game system and run it to my STR-DG910, after reading around about LPCM and Bitstream I went out and purchased an HDMI cable and ran LPCM.

Am I correct to assume that the higher bit rates from lossless audio etc actually bring with them more sound adding a higher level of depth and range to the audio or is it somewhat of a "placebo" effect?

Really appreciate any help I can get, tried Google but its hard to get straight answers.

Thanks!

The lossy codecs, Dolby Digital EX and DTS-ES, encode the information in the back channel (either one or two speakers) into the surround left and surround right channels. Because the surround back channel is not a discrete channel, the correct way to refer to these two formats is “Dolby Digital 5.1 EX Matrix” and “DTS 5.1 ES Matrix”. It would be misleading to refer to them as 6.1-channel or 7.1-channel formats.

However, DTS has a codec with a discrete full-bandwidth surround back channel, independent from the surround left and surround right channels. This is called DTS-ES Discrete 6.1.

The lossless high-def audio codecs support discrete full-bandwidth for all the channels.

Optical and Coaxial Digital cables can carry multi-channel signals for lossy Dolby Digital and DTS Digital. They cannot carry signals for Dolby Digital Plus, DTS HD High Resolution, Uncompressed LPCM, Dolby TrueHD, and DTS HD Master Audio. You need an HDMI cable.

Read the following thread. It will answer most of your questions.
https://forum.blu-ray.com/showthread.php?t=41820