An Attempt to Explain High Definition Audio

Hello all and please help! I am an amateur here and have posted this in other spots but not getting any help. Yes I have read through pages of this stuff but still not sure if I am grasping it. Thought a direct answer would help.

I have the BDP S360 blu ray. My Yamaha v550 amp does not connect via HDMI. I know my s360 decodes True HD and DTS-MA but won't do me any good here correct?

Anyway I am connecting to my receiver via Optical toslink. What is the best setup for me downmix pcm's or set it to DD and DTS. I assume downmix is wrong but want to make sure.

another thing with my receiver(amp). It is a 6.1 surround receiver and I have the 6th speaker connected. If you are familiar with yamaha you would know that there is a light indicator in the bottom right corner of the display which indicates the speaker output being used at the time (L/R stereo, 5.1, or 6.1). No matter what I set it to the SB(surround back) light never turns on??? I change many settings and it will not activate. However I hear the SB speaker working. The only time I have ever seen the SB light on is during the THX surround sound test at the beginning of star wars revenge of sith. The DVD says it is 6.1 audio on the cover. once the movie begins... the SB light turns off. Is this weird? Am I doing something wrong.

I know it is an old receiver but it does do a good job. Can someone help me out.

Darryl
 
Can someone confirm the point of dts-ma?

I remember with dvd it offered better quality than dobly digital, now that difference no longer exists between dts-ma and tru-hd; what differentiates the 2 to justify/keep dts in business?
 
Can someone confirm the point of dts-ma?

I remember with dvd it offered better quality than dobly digital, now that difference no longer exists between dts-ma and tru-hd; what differentiates the 2 to justify/keep dts in business?

No difference?
Dolby TrueHD:
• OPTIONAL support on BD players
• Compressed Lossless encoding
• Supports up to 8 channels of discrete audio
• Sample rates: 48, 96, 192 kHz
• Bit Depth: 16, 20, 24 bit
• Constant bit rate of up to 18.4 Mbit/s


Dolby TrueHD is a "lossless" compression codec. It is compressed to take up less disc space than a PCM track, but once decoded it is bit-for-bit identical to the studio master at either 16-bit or 24-bit resolution (at the discretion of the studio) and a bit rate up to a maximum of 18.4 Mbps.



DTS-HD Master Audio:
• OPTIONAL support on BD players
• Lossless encoding
• Supports up to 8 channels of discrete audio
• Sample rates: 48, 96,192 kHz
• Bit Depth: 16, 20, 24 bit
• Constant bit rate of up to 24.5 Mbit/s

DTS-HD MA (previously known as DTS+) is a lossless audio codec similar to Dolby TrueHD. Like Dolby TrueHD, a disc encoded with DTS-HD MA delivers ALL of the information from the original master recording — bit-for-bit. The difference between the two is that DTS-HD MA uses a core+extension configuration (just like DTS-HD HR). A DTS-HD MA track takes up more disc space than a TrueHD track, but does not require a secondary standard track for backwards compatibility. Since both DTS-HD MA and TrueHD are lossless, they are both 100% identical in quality to the studio master, and hence identical in quality to each other (lossless 24-bit/192 kHz).

They bth also use different proprietary methods of encoding, which may or may not result in better encoding when compared to the other. You decide ;)
 
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No difference?

They bth also use different proprietary methods of encoding, which may or may not result in better encoding when compared to the other. You decide ;)

Seems to me like DTS is playing off its old dvd advantage to sell its new technology with no advantage over tru-hd

Actually it seems like it comes at a cost as it consumes more disc space which could be used for something else with no benefit.

Im assuming this is like comparing zip and rar file compression. The compression styles are different and 1 produces a smaller file size over the other (i think) and i think one is faster but at the end of the day the decompressed output file is identical

This being said the only advantages of one over the other could be:
1) compressed file size for transport
2) power needed to decompress
3) capatibility

I remember paying alot more for a dts version of a dvd, i better make sure i dont get into the same situation paying more for a dts-ma version of a bluray is a tru-hd version is available
 
... i better make sure i dont get into the same situation paying more for a dts-ma version of a bluray is a tru-hd version is available
I don't think that will ever be an issue, as studio's usually choose one over the other and don't offer blu-ray releases with a choice... i don't think. ;)

on a personal note: I have a belief that dts-ma has a better balance (centre, fronts, surround) than truehD, which seems to favour front\rear over centre! I haven't tested my theory and it's just an opinion...

It may be a good topic for another thread though. :)
 
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DTS MA actually uses less space than True HD when you take into consideration the core structure of the format. TrueHD is nothing more than TrueHD while every instance of DTS MA will and does include a standard definition DTS encoding at its core for backward compatibility. A disc using Dolby's TrueHD must also include an entirely different standard definition Dolby Digital encoding in order to provide backward compatibility. The DTS structuring offers more scope for future expansion as well as backward compatibility.
 
DTS MA actually uses less space than True HD when you take into consideration the core structure of the format. TrueHD is nothing more than TrueHD while every instance of DTS MA will and does include a standard definition DTS encoding at its core for backward compatibility. A disc using Dolby's TrueHD must also include an entirely different standard definition Dolby Digital encoding in order to provide backward compatibility. The DTS structuring offers more scope for future expansion as well as backward compatibility.

Ahh i see, so as a whole its smaller in size.

Thanks. i feel much more comfortable about the new formats.
 
Hi dante01 - long time no post!:hiya: Hows the gerbils?! Or was it hamsters?

Just thought I'd draw your attention to the thread below in which it has been suggested hd audio via multichannel analogue outputs of a blu ray player may not be the same as that via hdmi.

Obviously, this is news to (all?) of us and more discussion is required but, already there are a couple of graphs you might wanna take a look at?

http://www.avforums.com/forums/audi...-vs-bitstream-off-topic-posts-ada-thread.html

Cheers
 
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Hi dante01 - long time no post!:hiya: Hows the gerbils?! Or was it hamsters?

Just thought I'd draw your attention to the thread below in which it has been suggested hd audio via multichannel analogue outputs of a blu ray player may not be the same as that via hdmi.

Obviously, this is news to (all?) of us and more discussion is required but, already there are a couple of graphs you might wanna take a look at?

http://www.avforums.com/forums/audi...-vs-bitstream-off-topic-posts-ada-thread.html

Cheers

Ferrets :rolleyes:

Dunno, but they appear to have totally forgoten about clock sync and jitter? I doubt there's any difference between the two data streams, but there may be differences in audio quality due to the different interfaces being used o convey them? They seem to be comparing the results of two data formats via two different means of transfer, which isn't a very good way of doing things.? ;)

To make proper comparisons then you'd need to send both the decoded LPCM and raw formats via HDMI.
 
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Ferrets :rolleyes:

Dunno, but they appear to have totally forgoten about clock sync and jitter? I doubt there's any difference between the two data streams, but there may be differences in audio quality due to the different interfaces being used o convey them? They seem to be comparing the results of two data formats via two different means of transfer, which isn't a very good way of doing things.? ;)

To make proper comparisons then you'd need to send both the decoded LPCM and raw formats via HDMI.
hello, surely the LPCM, whether via HDMI or multi channel out should have a better/truer[?] sound if it's the raw sound track as recorded in the original sound suite. Or am i missing the point of the different decoded audio tracks available? sorry, this is not confusing in an obvious way, but it still perplexing.
 
hello, surely the LPCM, whether via HDMI or multi channel out should have a better/truer[?] sound if it's the raw sound track as recorded in the original sound suite. Or am i missing the point of the different decoded audio tracks available? sorry, this is not confusing in an obvious way, but it still perplexing.

What is being inferred is that a raw format converted to LPCM via a playback component is superior to a raw format directly bit streamed to an AV amplifier or processor for conversion and decoding. A format converted to LPCM should be bit for bit identical to the source it was derived from and therefore there should be no difference in quality.

All digital audio data is converted to PCM at some stage prior to the DAC. Some people seem to think that doing this externally or at source makes for better data. Computer science says otherwise ;)

I believe they may be confusing differences between the was used the convey these signals rather than actually comparing like for like?

AS for the difference between the raw formats (inc. PCM as a format), see the first post of the thread:

Linear PCM (LPCM):
• MANDATORY support on BD players
• Lossless encoding
• Supports up to 8 channels of discrete audio
• Sample rates: 48, 96, 192 kHz
• Bit Depth: 16, 20, 24 bit
• Constant bit rate of up to 27.7 Mbit/s

A PCM track is an exact replication of the studio master, encoded on disc without compression. The benefit to this is that it maintains the purity of the source without any loss of fidelity that may come from compression. The downside is that an uncompressed audio track takes up a tremendous amount of disc space, which may (especially on single-layer BD25 discs) negatively affect the video quality of the movie. While the Blu-ray format is capable of utilising PCM audio up to 24-bit resolution, studios may choose to encode at 16-bit resolution instead, depending on the bit depth of the original source or concerns about conserving bandwidth (downsampling a 24-bit master to 16 bits is technically not the same thing as compression). 



Dolby TrueHD:
• OPTIONAL support on BD players
• Compressed Lossless encoding
• Supports up to 8 channels of discrete audio
• Sample rates: 48, 96, 192 kHz
• Bit Depth: 16, 20, 24 bit
• Constant bit rate of up to 18.4 Mbit/s


Dolby TrueHD is a "lossless" compression codec. It is compressed to take up less disc space than a PCM track, but once decoded it is bit-for-bit identical to the studio master at either 16-bit or 24-bit resolution (at the discretion of the studio) and a bit rate up to a maximum of 18.4 Mbps.



DTS-HD Master Audio:
• OPTIONAL support on BD players
• Lossless encoding
• Supports up to 8 channels of discrete audio
• Sample rates: 48, 96,192 kHz
• Bit Depth: 16, 20, 24 bit
• Constant bit rate of up to 24.5 Mbit/s

DTS-HD MA (previously known as DTS++) is a lossless audio codec similar to Dolby TrueHD. Like Dolby TrueHD, a disc encoded with DTS-HD MA delivers ALL of the information from the original master recording — bit-for-bit. The difference between the two is that DTS-HD MA uses a core+extension configuration (just like DTS-HD HR). A DTS-HD MA track takes up more disc space than a TrueHD track, but does not require a secondary standard track for backwards compatibility. Since both DTS-HD MA and TrueHD are lossless, they are both 100% identical in quality to the studio master, and hence identical in quality to each other (lossless 24-bit/192 kHz).


The three lossless audio formats associated with Blu-ray players' high-resolution audio soundtracks are Dolby TrueHD, DTS-HD MA and PCM. These formats will all convey 8 discrete channels (7.1) of "lossless" audio that exactly duplicate the original studio masters.


Bitstream is usually the output of an audio or video encoder. The elementary stream contains only one kind of data, e.g. audio, video or closed caption. An elementary stream is often referred to as "elementary", "data", "audio", or "video" bitstreams or streams. The format of the elementary stream depends upon the codec or the type of data carried in the stream itself. The Source device does not decode the signal and the device receiving the bitstream must be capable of decoding it. Think of bitstreaming as passing data through untouched. For example, if your Blu Ray player cannot decode Dolby TrueHD / DTS-HD Master Audio but your AV receiver can, you need to set the digital output of your player to "Bitstream". In other words, the encoded audio will be streamed to the AV receiver / amp in order for it to do the decoding.

Linear pulse code modulation (LPCM) is a method of encoding audio information digitally. The term also refers collectively to formats using this method of encoding. LPCM can be included on the disc itself or the player can derive LPCM from other digital tracks if it posses the ability to decode them. The player then transports the raw LPCM or decoded as LPCM audio through the player's digital connections to other devices such as an AV receiver. For example, if your Blu Ray player can decode Dolby TrueHD / DTS-HD Master Audio but your AV receiver can't, you need to set the digital output of your player to "LPCM" or "PCM". In other words, the encoded audio will be decoded by the player in order for it to be streamed to the AV receiver / amp as LPCM.

LPCM is used for the lossless encoding of audio data in the compact disc Red Book standard and has been defined as a part of the DVD and Blu-ray standards as well as the digital audio standard frequently called AES/EBU. Stereo LPCM is one of the mandatory audio formats that all DVD players and processors must support.

The term PCM is often used to describe data encoded as LPCM. PCM is a digital representation of an analog signal where the magnitude of the signal is sampled at regular intervals and then mapped (quantized) into binary code. The quantization is necessary because CPUs are used to implement DSP (Digital Signal Processing). Computers can only process finite quantities at any one time. Signals need to be mapped to fit a finite resolution, so that they can be stored in a CPUs registers and memory while the DSP takes place. PCM ís basically a stream of "1s" and "0s" (bits, "ons" and "offs") that precisely describe the frequencies and relative loudness (amplitude) of a music signal. No data is discarded to conserve bandwidth or reduce file size. The "1s" and "0s" are used by the DAC to reconstruct the original audio in order that the original audio may then be amplified and output as analogue by your AV amp or receiver.

Quantization is the fundamental element that distinguishes lossy data compression from lossless data compression, and the use of quantization is nearly always motivated by the need to reduce the amount of data needed to represent a signal.

Aimost all new BD players can decode the Dolby TrueHD / DTS-HD MA lossless audio and send it to your receiver as a multichannel LPCM stream. Just about any modern AV receiver can decode LPCM even if unable to decode Dolby TrueHD / DTS-HD Master Audio. The LPCM audio is identical to the Dolby TrueHD / DTS-HD MA original format, so no quality is lost.
 
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I hate that thread but the original point is:

certain Blu-ray players had measurably different signals on their own analogue outputs when compared to the analogue output of a processor playing back the same "HD Codec" track.

Draw your own conclusions as to why that may be the case.
 
I hate that thread but the original point is:

certain Blu-ray players had measurably different signals on their own analogue outputs when compared to the analogue output of a processor playing back the same "HD Codec" track.

Draw your own conclusions as to why that may be the case.
can we assume that when you say "measurably different", you mean inferior?
 
Simple question for those who have upgraded.
can you actually tell the difference between HD sound and standard 5.1 from a DVD?

I'm thinking of upgrading my AVR250 to a more up to date receiver.

Cheers Phil
 
Simple question for those who have upgraded.
can you actually tell the difference between HD sound and standard 5.1 from a DVD?

I'm thinking of upgrading my AVR250 to a more up to date receiver.

Cheers Phil

i upgraded about 6 months ago and my "Up" on BD vs DVD (Got it as gift) seems to have a much wider range and the rears seem to be more discrete.

Fronts and centre are marginal and maybe sub channel is a bit tighter.

I dont have any other Dvd to compare to and the bluray i have only have english in the tru-hd or dts-ma or stereo

Avatar sounds amazing, but thats probably just avatar and not the sound format.
 
Simple question for those who have upgraded.
can you actually tell the difference between HD sound and standard 5.1 from a DVD?

I'm thinking of upgrading my AVR250 to a more up to date receiver.

Cheers Phil

I think there's an actual real-world difference between DTS and DTS HD MA, as well as between DD and DD-True HD

I'm using 5.1 on my setups (see sig).

In my opinion....voices are better imaged in general and clearer. Ambient surround sounds like music (for instance music behind you in a scene), is more pronounced and surround effects seem better placed. Things like shards of glass flying around seem to be so clear you can imagine where they're falling around you.

The standard def sound formats have these, but in general (to my ears/senses), they seem more 'real' and more placed in the sound field.

LFE is also harder hitting and more controlled.

All this is for me and only really comes out properly in my full, but cheapish), setup. I do notice the difference though.
 
I personally think that when you 'upgrade' there is an expectation of better 'performance' and therefore you may perceive an enhancement, when maybe there is none (or very little) to the human ears - especially when they are 55 years old !!!
 
I personally think that when you 'upgrade' there is an expectation of better 'performance' and therefore you may perceive an enhancement, when maybe there is none (or very little) to the human ears - especially when they are 55 years old !!!

Maybe for some, but I was fully ready to take my shiny new amp back to the store if I'd not noticed a difference.
 
Receiver: Yamaha RX-V467
TV: Toshiba 55G300U
PS3

I have everything set per the video on the first page. Yet, when i hit select on the PS3 remote it only shows it as "Dolby Digital" and not PCM or LPCM. I have tried switching my reciever to "direct" and "straight" but niether seem to work. What have I done wrong? I have 300 in and the Blu Ray says it supports TrueHD so I know I must have something set wrong. I've read pages and pages but all I can ever find is people whining about the TruHd light not coming on the receiver... so I know the answer to that. I wish I could get to the point of having that "problem".
 
Receiver: Yamaha RX-V467
TV: Toshiba 55G300U
PS3

I have everything set per the video on the first page. Yet, when i hit select on the PS3 remote it only shows it as "Dolby Digital" and not PCM or LPCM. I have tried switching my reciever to "direct" and "straight" but niether seem to work. What have I done wrong? I have 300 in and the Blu Ray says it supports TrueHD so I know I must have something set wrong. I've read pages and pages but all I can ever find is people whining about the TruHd light not coming on the receiver... so I know the answer to that. I wish I could get to the point of having that "problem".

The video shows settings for the older PS3 which cannot Bitstream HD audio. Is your PS3 the old model or the new Slim model? With the Slim PS3, setting the BD/DVD Audio Output Format (HDMI) setting to BITSTREAM enables the raw HD formats to be output via HDMI.

Note that BD titles with a TrueHD encoding require that you specifically select that format in the discs setup/options menu prior to playback. DTS-HD MA encoded audio is automatically prioritised and sent when a capable receiver is detected. If you don't select TrueHD then you get SD audio such as Dolby Digital.

Dolby Digital is an SD format and neither PS3 models have issue with streaming non HD formats. The PS3 is sending Dolby Digital because you didn't select TrueHD as the desired audio via the disc's menu prior to playback. Set the BD/DVD Audio Output Format (HDMI) setting on the PS3 to LPCM. Select TrueHD as the format via the 300 BD's menu and play the film. PCM should appear on the amp rather than TrueHD ;)

Also ensure that the amp's HDMI audio output is set to just AMP and not AMP+TV.
 
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The video shows settings for the older PS3 which cannot Bitstream HD audio. Is your PS3 the old model or the new Slim model? If you've the Slim PS3, set the BD/DVD Audio Output Format (HDMI) setting to BITSTREAM and you should then get the raw HD formats streamed to the amp. Also note that BD titles with a TrueHD encoding require that you specifically select that format in the discs setup/options menu prior to playback. DTS-HD MA encoded audio is automatically priotised and sent when a capable receiver is detected.

Dolby Digital is an SD format and neither PS3 models have issue with streaming non HD formats. The PS3 is sending Dolby Digital because you didn't select TrueHD as the desired audio via the disc's menu prior to playback. Set the BD/DVD Audio Output Format (HDMI) setting on the PS3 to LPCM. Select TrueHD as the format via the 300 BD's menu and play the film. PCM should appear oin the amp rather than True HD ;)

Also ensure that the amp's HDMI audio output is set to just AMP and not AMP+TV.



I actually have the older model I think. I don't know what the "slim" looks like but it does not say slim on the box. So I assume the older model. I now put in a different Blu Ray and it is displaying TrueHD. When I had 300 in it only displayed Dolby Digital. I'm a bit confued. Also with 300 I could not get to the typical menu. As for selecting TruHD in the menu, I didn't have to do it for the Blu Ray I have in now and it is working correctly. i have no clue *** is going on.
 
plus everything is set exactly as you mentioned above minus bitsteam since I have the older model PS3. I appreciate your help and the quick response.
 
plus everything is set exactly as you mentioned above minus bitsteam since I have the older model PS3. I appreciate your help and the quick response.

Reread my edited post and you'll have the solution o your problem.

Note the points made about having to select TrueHD as the desired audio ;)


The video shows settings for the older PS3 which cannot Bitstream HD audio. Is your PS3 the old model or the new Slim model? With the Slim PS3, setting the BD/DVD Audio Output Format (HDMI) setting to BITSTREAM enables the raw HD formats to be output via HDMI.

Note that BD titles with a TrueHD encoding require that you specifically select that format in the discs setup/options menu prior to playback. DTS-HD MA encoded audio is automatically prioritised and sent when a capable receiver is detected. If you don't select TrueHD then you get SD audio such as Dolby Digital.

Dolby Digital is an SD format and neither PS3 models have issue with streaming non HD formats. The PS3 is sending Dolby Digital because you didn't select TrueHD as the desired audio via the disc's menu prior to playback. Set the BD/DVD Audio Output Format (HDMI) setting on the PS3 to LPCM. Select TrueHD as the format via the 300 BD's menu and play the film. PCM should appear on the amp rather than TrueHD ;)

Also ensure that the amp's HDMI audio output is set to just AMP and not AMP+TV.
 
Reread my edited post and you'll have the solution o your problem.

Note the points made about having to select TrueHD as the desired audio ;)
As I stated it does not give me the option to select the desired audio format in the discs start up menu. 300 goes directly into the movie. When I bring up the "pop up menu" it does not have an option anywhere to change to TrueHD. I can change the scene, language, and watch the special features. That is it. However when I put in Across the Universe there was a normal menu before the movie started. Again no option to select the sound format, however it played in TrueHD correctly. I know you might say 300 might not have the option to play in TrueHD, but it does. It's the first format listed on the back of the case.
Trust me I have everything set as you descirbed and I know exaclty what you mean, but the option isn't there for 300 and I don't get it.
 

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