Does copy protection diminish sound quality?

[Lasersnuser]

I recently received David Gray's "A New Day at Midnight" on DVDA. I've not been able to give it a thorough listening yet, but the first impression of the 5.1 96 kHz/24 bit track is good.

I noticed, however, that the disc has copy protection. I also remember reading on the HTF-forum that someone felt this diminished sound quality in general, and specifically on the David Gray DVDA.

Could anyone explain how this works technically, and if copy protection actually causes loss in sound quality?

Thanks in advance for any help!

Mitch

[CCarncross]

IMO, copy protection does not affect sound quality, in fact all SACD and DVD-A titles that I know of are encrypted/and copy protected. In the old days, lots of people complained that macrovision screwed up their PQ, but most of this was due again IMO to poor display devices...actually incompatible display devices. I have yet to see any proper tv or display that had a problem with macrovision.

[tunerguy]

The way that it would affect it is in the cd incryption.It has short periods of nothing recorded.It's supposed to screw with burners that record on high speed.DVD-a & SACD cannot be burned.

[CCarncross]

Tunerguy, how does that affect the sound quality for playback though?

[Dan Hitchman]

Aren't you confusing encryption with audio watermarking?

Watermarking can and does effect sound quality since it is applied into the audio chain itself. That's why some recording companies don't use it.

I wish no one did.

[Lasersnuser]

Yes, this is what I meant. Is it then technically correct to conclude that copy protection by encryption does not affect sound quality whereas protection by watermarking does?

How can you tell if a disc is protected by watermarking?

The David Gray DVD-A simply states "This DVD is copy protected". Is Warner known to use watermarking?

Mitch

[Dan Hitchman]

I don't think they say. Watermarking can be applied to any medium, CD, DVD, DVD-Audio, SA-CD, etc. I don't understand why they would add something to the audio stream that would have a negative impact on sound quality, but they do. A-holes!

I had heard that at DVD-Audio's inception that DTS Entertainment, for one, said they would not use audio watermarking.

The type used is called Verance, I believe.

Encryption basically scrambles the signal at the source and the other end has to have the official key code to unlock the data for use (in a way just like a scrambled HBO signal). It doesn't effect quality one way or the other. That's why many in Hollywood want HDMI as it uses an encrypted digital stream as part of the cable interface's specs.

Think of audio watermarking like Macrovision for the video portion of DVD's. It is embedded into the data itself and effects it.

[Lasersnuser]

Well, I've spent some time listening to David Gray's "A New Day at Midnight" DVDA and cannot detect anything wrong with the audio due to the copy protection. I have noticed, though, that the player pauses and searches between each track. I haven't noticed this on any other DVDAs. Perhaps the kind of encryption used here is the one where there are short periods of nothing recorded, as mentioned by tunerguy.

Then again, there is of course no way of knowing how the DVDA would have sounded without copy protection. But as mentioned I can find no evidence of it affecting sound quality in this case.

I have furthermore compared the DVDA to the CD and to my ears both the 192/24 stereo and 96/24 surround tracks are noticeably better than the CD. So, for fans of mr. Gray I would certainly recommend the DVDA!

Mitch