VR2090 vs. TXDS656 vs. AVR65

Posted by SMR [WizOp] [IP: 195.232.122.201] on October 28, 1998 at 14:52:25:

In Reply to: VR2090 vs. TXDS656 vs. AVR65 posted by Joe on October 28, 1998 at 02:16:11:

Joe,

: Naive questions: To what extent will DTS be compressed on DVD's in comparison to DD?

Dolby Digital on DVD runs at either 384kb/s or 448kb/s. DTS is said to run at the same rate it does on laserdisc, namely 1.536Mb/s.

: Isn't it considered to deliver higher resolution because it isn't as compressed?

Exactly. Whether it does or not is debatable, the perceptual coding model used to compress the data is equally as important. If that is inferior to Dolby's model then DTS need a higher bit-rate to achieve the same fidelity. Incidentally, controlled tests have never separated the two, listeners can't specify a preference one way or the other.

: (what is the rate for each, anyway?)

DTS is 48kHz 20-bit, Dolby Digital can be 48kHZ 24-bit.

: Someone I spoke with suggested that it will be compressed more on DVD than it is on LD.

That's possible, DVD can only deliver a certain amount of data at a time, and that includes the image information. If, as DTS claim they're going to use the maximum video data rate they may need to save some bandwidth by reducing the audio data rate. I think it's unlikely though, they run the risk of making DTS sound inferior to Dolby Digital.

: This person also suggested that this was a lossless bit-for-bit compression/decompression, which I found a little difficult to believe…

No, DTS on LD, music disc and DVD will be lossy. The format can be loss-less, but requires the enormous data-rate of 4.096Mb/s, far too much for DVD to handle.

: Know of any websites that answer these kinds of basic questions?

You mean apart from this one? ;-) Try the DVD FAQ, the link is at the foot of this message.

: Word on the street, as I've heard it, is that DTS encoded DVDs will almost certainly NOT be on the market by Christmas, but that they have committed fairly firmly to January '99 (of course, given the history here, such commitments must be taken with a few grains or distilled grains...;) Have you heard similarly?

Yes, I've heard much the same regarding region 1 discs. However, I've just been handed a region 2 (Japanese) production disc. My Meridian 586 won't play it though - which is ironic if you think about it. ;-)

Stuart.

• Internet DVD FAQ

Follow Ups:

Return to the new SMR Forums Menu

Design & HTML © SMR Home Theatre, Images © SMR Home Theatre cannot be reproduced without permission.  The images on this page are digitally watermarked.  New forum messages should be posted into SMR Forums v2 - http://www.smr-forums.com/

	The Web   SMR Archive