dvd sound.....stinks! (1 Viewer)

[Lew Crippen]

I have a number of DVDs with PCM audio. They are pretty much all opera. Which goes along with ‘music only’ statement made earlier.

 

[Tony Kwong]

IMO, and on my system the LD the SPEED PCM track is great, but the AC-3 LD looses something. The DTS LD sounds a little bit better in some scenes than the AC-3 LD. The Five Star Edition DVD mix is a bit more active, but doesn't sound as full.

The Piano and True Lies both have great PCM tracks! Sometimes I don't even bother with the AC-3 on the LD!

 

[John Kotches]

Clarification on bit rates. 384K is used when the input sampling rate to the encoder is 44.1K. 448K is used when when the input rate to the encoder is 48K.

It's a matter of what tradeoffs you are willing to make when creating a DVD. You have a finite bandwidth for use, which can be taken up by audio, video or a combination of both. 16/44.1K takes up 1.5MB/second of the available bit rate. MPEG encoding is variable rate, with an aggregate bandwidth average (target) somewhere between 5 and 6Mbits/second. This leaves only about 3.5-4.5Mb/second (on average) to carry the video information. If you slap on a DD5.1 track, you are down to about 3-4Mb/second average bit rate. Needless to say, that's a huge hit on PQ.

It's a serious juggling act between PQ and Audio since you're dealing with a finite bandwidth. I notice not too many are complaining about video compression, where the compression ratio is ~50:1 for uncompressed vs. compressed video streams.


Regards,

 

[Chris Brown]

I absolutely love the sound on my laserdiscs. Doing a direct comparison between the SW Phantom menace DVD and Laserdisc on my system, the LD sounded a lot better (And yes I know the LD is mastered a little hot and did compensate with more volume on the DVD). Although… there are some DVD’s that sound great also, I have no complaints.

 

[Adam Barratt]

16/44.1K takes up 1.5MB/second of the available bit rate.

48kHz would be the closest option available on DVD-Video.

Adam

 

[John Kotches]

Adam,
I'll clarify input rates / output rates with Roger Dressler @ CES, -- I've been informed exactly what I stated. Seems like he's a good person to clarify. What might be the case is that I'm being informed of common practice vs. actual requirements.
The 48K sampling rate requirement makes it a little uglier for bandwidth when utilizing PCM
Regards,

 

[Vince Maskeeper]

John,

I'm not sure what Roger said- but I rip DVD 384 tracks which are 48k sourced all the time. Furthermore- on software based encoders regardless of sample rate- all the bitrate versions are available.

The same is true of most lossy compression schemes like this. MP3, for example, can encode any sample rate at data rate-- I painfully discovered this after encoding several audio commentaries as MP3 from 48k source at 128kbps only to find my car MP3 player did not support the 48k tracks.

-Vince

 

[John Kotches]

Vince,

Roger D didn't say anything to me on the topic. I was informed of this by a 3rd party. Since I have a session with Roger @ CES scheduled already to discuss what the future might bring for audio products from Dolby I figured I'd take advantage of my time to sneak in this question.

Regards,

 

[Brian Ruth]

Regarding Loss:

I would THINK that full-bitrate (~1510 kpbs) DTS would help a bit. While there aren't very many full-bitrate DTS soundtracks out there (the Dune miniseries SE is the only one I think I have in my collection), it probably goes a long way towards maintaining sound quality if it's done right. If I'm not mistaken, full-bitrate DTS uses SLIGHTLY more bandwidth than CD audio, though it has to reproduce 5 channels instead of 2.

Unfortunately (for audiophiles at least), it seems like most studios are more comfortable giving the extra 700 kbps that a half-bitrate DTS gets them to the Video presentation.

 

[Joe Cole]

I would THINK that full-bitrate (~1510 kpbs) DTS would help a bit. While there aren't very many full-bitrate DTS soundtracks out there (the Dune miniseries SE is the only one I think I have in my collection), it probably goes a long way toward maintaining sound quality if it's done right.

Isn't the DTS version of Saving Private Ryan done in the higher bit rate? And it does sound better to me.
As a owner of and former user of LDs (only Star Wars any more) I'd have to say that LD did sound a little better. Actually a good friend (who brought me into this consuming hobby) and I were disappointed with the audio side of the new (at the time) DVD format. DVD was a little lifeless sounding in a direct comparison to LD. But I finally gave in (quicker than my friend) because of the video quality and most importantly the price of movies. 40% cheaper is enough incentive for me to ignore the slight difference in sound.
Besides, if it sounds lifeless just turn it up and your bleeding hears won't tell the difference any more.

 

[Michael Reuben]

Isn't the DTS version of Saving Private Ryan done in the higher bit rate? And it does sound better to me.

The DTS track on SPR used a different mix, which most people find superior.

M.

 

[Adam Barratt]

Saving Private Ryan's DTS soundtracks uses the lower 754kbps bit-rate.

Adam