Answers to HD-A1 and HD-XA1 Audio Questions - Page 14

Originally Posted by FilmMixer

I agree Earz... and I can get the best now with HDMI 1.1, and it won't change with HDMI 1.3 That's my whole point.... Now where are the True HD decoders?

Originally Posted by Earz

With at least a few posters noticing lip sync issues on the Serenity disc, wouldn't hdmi 1.3, with its built in ability to fix sync issues be a good thing?

Originally Posted by Roger Dressler

It is not a codec issue. It is the player format that governs how audio is handled.

Originally Posted by DaViD Boulet

Roger,

are you saying that an HD DVD/BD player could pass the "pure" DTS HD/DD True HD signal via HDMI (without unfolding to LPCM) 1.3 even with advanced content authoring without messing around with anyone's spec? That way an audiophile could avoid having the player remix/process the high-res lossless audio...for instance?

dave

.....the fact that players will be mixing the audio internally means that it will no longer be possible to output the raw bitstreams from the player as is customary with DVD-Video. Instead, these players will decode and mix in standard PCM format, and therefore will have the option to output the PCM digital signal either directly, or through DACs as analog signals to the connected audio receiver. It should be mentioned that certain discs and players will indeed support the direct output of encoded audio bitstreams, but this option is the choice of the content maker.

.......

Many advanced A/V receivers and processors manufactured today have six (or even eight) channels of external analog audio input for high-resolution DVD-Audio or SACD playback; these will work equally well for multichannel analog-equipped HD disc players, and enable consumers to take advantage of the full-bandwidth audio performance available in next- generation formats without having to upgrade their A/V systems. A growing number of A/V receivers include HDMITM (1.1) inputs, providing a direct digital connection for the new optical disc players. This ensures not only that the full quality of the HD formats will be available, but that any digital postprocessingsuch as bass management, room compensation, speaker equalization, Dolby Pro Logic® IIx processing, and otherscan be performed in the A/V processor directly on the source audio without any extra analog and digital conversion steps along the way.

.............

One additional consequence of the above rapidly becomes apparent: there will be no particular reason or benefit to decoding native audio bitstreams in the A/V receiver. This means A/V receivers with HDMI digital inputs or analog-to-digital converters for their analog inputs will be able to use their DSP resources to postprocess full-bandwidth audio from the players, rather than being required to also handle core bitstream decoding duties. (Such postprocessing is often done at a sampling rate of 96 kHz, thereby demanding at least double the DSP horsepower of conventional postprocessing done at 48 kHz.)

Originally Posted by FilmMixer

Exactly how I feel.. It's about value, and with these new formats, Dolby and DTS have put the burden on the player manufacturers to do the heavy lifting, which should be the cheapest component to replace...

Originally Posted by kjack

Actually, they put the burden on the decoder chip manufacturers. We are having to include almost all the audio processing an AVR does, plus handle the new audio formats. While keeping lip sync regardless of what the audio and video processing is doing. Then adding user adjustable audio delay to compensate for video processing delay inside the HDTV.

Originally Posted by Earz

With at least a few posters noticing lip sync issues on the Serenity disc, wouldn't hdmi 1.3, with its built in ability to fix sync issues be a good thing?

Originally Posted by kjack

We are having to include almost all the audio processing an AVR does, plus handle the new audio formats. While keeping lip sync regardless of what the audio and video processing is doing. Then adding user adjustable audio delay to compensate for video processing delay inside the HDTV.

Not speaking for Roger but here it is again

DD+ or TRUEHD Bitstream over HDMI 1.3 = ONLY AVAILABLE IF THE DISC IS AUTHORED AS BASIC...

One additional consequence of the above rapidly becomes apparent: there will be no particular reason or benefit to decoding native audio bitstreams in the A/V receiver.

Originally Posted by DaViD Boulet

FilmMixer,

But Roger seemed to state that this was *player* depenedent, not something that was part of the spec or a player requirement.

It says it right there in the quote I gave you : "but this option is the choice of the content maker."

It is not a codec issue. It is the player format that governs how audio is handled.

But I think that you are worrying about losing fidelity, and while that may be a possibility, I don't think that it will be an issue...

Originally Posted by RichB

I cannot get the Analog outputs to work. It there a trick?

- Rich

Originally Posted by DaViD Boulet

...I'm just asking for clarity given that it seems both comments imply slightly different requirements...

Originally Posted by DaViD Boulet

I'm just asking for clarity given that it seems both comments imply slightly different requirements.

Originally Posted by DaViD Boulet

That is indeed my concern (given my experience with DTS versus DD and the "difference" that appears to often result from decoder-side dialog-normalization signal processing when the same master is used for both).

Originally Posted by FilmMixer

Another note.. I find it so funny that we now have the ability to decode a much higher quality track, and use full rate DTS encoding to get to legacy equipment, and everybody seem to be bitching about it..... I'll be curious to hear how this re-encoding sounds in comparison to the PCM decode.

Originally Posted by FilmMixer

Another note.. I find it so funny that we now have the ability to decode a much higher quality track, and use full rate DTS encoding to get to legacy equipment, and everybody seem to be bitching about it..... I'll be curious to hear how this re-encoding sounds in comparison to the PCM decode.

Originally Posted by AndreYew

There are two things to worry about:

1. If the original soundtrack were lossy-encoded with either DD or DTS, another lossy encoding of it, as done by the Toshiba's DTS encoder, can exaggerate coding artifacts.

2. If the original soundtrack is PCM, then one has to wonder what quality of realtime DTS encoder is found in a $500 consumer device that has already blown lots of money on a 2.5 GHz Pentium 4, 1 GB of memory, a computer HD-DVD-ROM drive, and big fat FPGAs, among other things.

I guess the excuse is that one is listening to a backwards-compatible mode with S/PDIF, and should really get HDMI 1.1 to get the best quality.

--Andre

Originally Posted by AndreYew

There are two things to worry about:

1. If the original soundtrack were lossy-encoded with either DD or DTS, another lossy encoding of it, as done by the Toshiba's DTS encoder, can exaggerate coding artifacts.

2. If the original soundtrack is PCM, then one has to wonder what quality of realtime DTS encoder is found in a $500 consumer device that has already blown lots of money on a 2.5 GHz Pentium 4, 1 GB of memory, a computer HD-DVD-ROM drive, and big fat FPGAs, among other things.

I guess the excuse is that one is listening to a backwards-compatible mode with S/PDIF, and should really get HDMI 1.1 to get the best quality.

--Andre

Originally Posted by rdjam

No doubt the HDMI and analog choices are best quality.

But at least the DTS re-encoding option is there as an option for SPDIF.

I'm not an expert on this - but I would guess that since DD+ uses different encoding techniques than DTS, I would say that doing DD+, then DTS actually creates LESS artifacting that doing DD+ then DD would.

I don't think that the DTS encoding chip is of a low quality at all - reports are that it sounds pretty damn good on Serenity, and also passes 6.1 and 7.1 matrix information (someone reported getting 7.1 with Neo6, out of the 5.1 DTS encoding, and other reported IIx 6.1 decoding).