HDMI with optical audio?

[j_garcia]

DVDs generally don't have better sound than a well mastered CD, IMHO. With HD-DVD and Blu-ray, you have high def audio options and there is a noticeable difference with them most of the time vs the audio tracks on most DVDs. HDMI isn't going to make a difference for CD and DVD sound quality though IMO.

 

[GlocksRock]

How different is True HD vs. regular 5.1 via optical to the human ear?

You won't be able to get TrueHD via optical digital since it doesn't have the bandwidth, but TrueHD does contain the core Dolby Digital, so that's what you will get.

 

[mtrycrafts]

But what does that really mean, inasmuch as a regular DVD has sound quality significantly better than a CD?

DVDs use lossy, perceptually coded audio formats so it cannot be better than CD, unless the CD is poorly mastered.

 

[bmz]

This comes from an Audioholics article; and from this it appears that a DVD is superior to a CD:

Metric --------------------- DVD-------------CD

Sampling Rate ------ Up to 192 kHz-----44.1 kHz

Amount of Bits------- 16 to 24 bits------16 bits

Dynamic Range ---- 104 to 108 dB-----96 to 98 dB

Multi Channel Capability---- Yes-------Yes; but with very lossy compression

 

[bmz]

You won't be able to get TrueHD via optical digital since it doesn't have the bandwidth,

What, specifically is the bandwidth limitation; and is a coaxial digital cable better?

 

[bmz]

In view of the previous discussions, can anyone explain the following quote to me?

TI's Aureus processors are the first to support Dolby® Digital Compatible Output technology, which enables next-generation optical disc (HD DVD and Blu-ray) players to deliver a 640kbps Dolby Digital encoded surround sound signal and compatible playback through any existing Dolby Digital equipped audio/video receiver (AVR) with a digital audio input (S/PDIF or optical)

 

[j_garcia]

What, specifically is the bandwidth limitation; and is a coaxial digital cable better?

DVD is CAPABLE of being superior to a CD, but video content and audio content take up space, so audio compression techniques are the norm which means you will not always get the best audio around regardless of mastering. DVD-Audio and SACD are examples of lossless audio and they cannot be passed via S/PDIF (optical, coaxial) connections.

There is no difference in the capabilities of optical vs coaxial technically speaking both are categorized for the same data transfer. Both are limited to 24 bit max, though I don't know that this would be a limiting factor. I found it at one point, however I can't seem to find the total bandwidth now for some reason. The issue I believe is that the available bandwidth for so many channels is where the standard digital connections are limited. You can send lossless PCM tracks via standard S/PDIF but you will only get stereo out the other side because it "ignores" the other channels as they cannot be transmitted.

Dolby True HD and DTS-HD MA are both backwards compatible in that they can send a down converted "core" 5.1 stream via standard S/PDIF.

 

[mtrycrafts]

In view of the previous discussions, can anyone explain the following quote to me?

That quote must be from the past just before or at the time of the hi def formats coming out.
TI is able to pass or process the DD at the higher bit rates, 640kbs, and pass it through the digital audio out. And, receivers already has that capability programmed into their chips to decode the higher DD rates. This is DD+

 

[mtrycrafts]

This comes from an Audioholics article; and from this it appears that a DVD is superior to a CD:

Metric --------------------- DVD-------------CD

Sampling Rate ------ Up to 192 kHz-----44.1 kHz

Amount of Bits------- 16 to 24 bits------16 bits

Dynamic Range ---- 104 to 108 dB-----96 to 98 dB

Multi Channel Capability---- Yes-------Yes; but with very lossy compression

Yes, this applies to music discs, not movies. I still think of DVDs as video movie discs. The audio is called by their other names, DVD-A or SACD.

 

[mtrycrafts]

Oh ok thanks guys

but I thought OPPO 981 is a High def player....

Edit: oh nvm, you meant the movies itself...i misread it

thanks

I am sure it just up-samples standard def DVDs. It will not play hi-def DVDs, HD/BD.

 

[bmz]

DVD is CAPABLE of being superior to a CD, but video content and audio content take up space, so audio compression techniques are the norm which means you will not always get the best audio around regardless of mastering.

I don't understand the technology. If I play a HD-DVD, video by HDMI, and audio by SPDIF, why does the video take space from the audio?

BTW, mtrycrafts: the original table I used listed "DVD/DVD-A" as the same audio quality.

 

[mtrycrafts]

I don't understand the technology. If I play a HD-DVD, video by HDMI, and audio by SPDIF, why does the video take space from the audio?
.

I think he meant space on the DVD itself. It has a finite storage capacity. This gets divided between video and audio. Standard DVDs had the standard audio as DD5.1 max, then added the 6th ch. DVDs have limits on data storage.
HD/BD-DVD came with lots more capacity, so more video bandwidth and audio bandwidth. Now, if a movie is long, like Transformers, to get a good video at 1080p without much data losses, audio storage space was not able to support the True HDDD.

 

[mouettus]

*THREAD - PAUSE*

Hey guys, don't want to hijack the thread but speaking of lossless, would I be able to receive TrueHD and DTS-HD MA via HDMI (PCM stream decoded from an hi-def player) to an Harman/Kardon AVR-347? (HDMI 1.1) If so, I'm buying one tomorrow.

*THREAD - PLAY*

 

[bmz]

Just bought a Toshiba HD-DVD player($197@Amazon) here's what a review says about about the audio over a Toslink connection:

DD+ or TrueHD signals are decoded and converted to PCM in the player. This PCM signal is then re-encoded as a 1.5 Mbps DTS bitstream, which is then output over the Toslink connection and decoded yet again from DTS to (ultimately) analog by your AVR or pre/pro.

Can any of you experts interpret that for me?

 

[jonnythan]

HDMI > optical

 

[bmz]

Jonnythan:

Maybe not-

DTS 96/24 offers the following:
* Sound quality equivalent to the original 96/24 master.
* Full backward compatibility with all existing decoders. (Existing decoders will output a 48kHz signal.)
* No new player required: DTS 96/24 can be carried on DVD-Video, or in the video zone of DVD-Audio discs that is accessible to all DVD players.
* High resolution 96/24 5.1-channel sound with full-quality full-motion video for music programs and motion picture soundtracks on DVD-Video.
* Digital 96/24 output through the S/P DIF port.

 

[j_garcia]

Yes, but the problem isn't that optical isn't capable of good sound, it is that 1)the data for that audio is large, therefore takes up space on the disc (DVD) and 2) at the highest rates with multiple channels the data WILL exceed the bandwidth of S/PDIF. Multichannel lossless PCM already exceeds the capabilities.

 

[bmz]

Yes, but the problem isn't that optical isn't capable of good sound, it is that 1)the data for that audio is large, therefore takes up space on the disc (DVD) and 2) at the highest rates with multiple channels the data WILL exceed the bandwidth of S/PDIF. Multichannel lossless PCM already exceeds the capabilities.

I understand the theory of what you are saying. But Toshiba says that it decodes the TrueHD signal from the HD-DVD and then re-encodes it to 1.5 Mbps DTS bitstream, which DTS says can be done as essentially lossless 5.1 and outputted on Toslink. Does anyone know how Toshiba re-encodes the TrueHD?

 

[mtrycrafts]

I understand the theory of what you are saying. But Toshiba says that it decodes the TrueHD signal from the HD-DVD and then re-encodes it to 1.5 Mbps DTS bitstream, which DTS says can be done as essentially lossless 5.1 and outputted on Toslink. Does anyone know how Toshiba re-encodes the TrueHD?

I don't have access to Toshiba's algorithms but I would say, they are in essence have a mini DTS encoder, they make it a lossy format, period, no matter how close they think it is to lossless audio.