DVD Audio or SACD ?
Reply #30 – 2005-03-27 21:11:45
Actually the hybrid CD/SACD disks have an interesting "protection", since a computer drive doesn't "see" the SACD layer, only the CD layer. [a href="index.php?act=findpost&pid=284780"][{POST_SNAPBACK}][/a] That's just one of the intellectual property protection schemes built into SACD. Another is physical (visible) watermarking of the disc, as well as data encryption. Since there is no such thing as an SACD "burner," there's less likelihood that an SACD disc will be trivially pirated, as is the case with the DVD family. As to which encoding method is "better," that’s a tough and lengthy discussion… First off, any reference to Lipshitz and Vanderkooy’s paper on the inability to optimally dither DSD data is inappropriate and outdated if you pay attention to current technology. As one of the few people who has taken the time to conduct extensive tests with both 192 kHz LPCM and single speed DSD with live sources (my company <www.sonicstudio.com > pioneered and manufactures both PCM and DSD professional production systems), I can say that they are subjectively different but both equally valid. As was pointed out in earlier postings, it's the details of the formats that really highlights the advantages of one over the other. The SACD format was designed, from the start, as backwards compatible with the Red Book spec. The Dual Disc "format" is a bolt-on afterthought that lacks compatibility with CD players due to the physical characteristics (thickness) of the discs. DVD-Audio also cannot deliver the highest fidelity LPCM in multichannel and is limited to 192 k stereo. All other factors being equal, 96 kHz LPCM does not sound as close to the source as DSD does, which means you are saddled with lesser quality 5.1 when listening to a DVD-A release. Production-wise, both 192 k LPCM and DSD make great origination formats; material can be transcoded into any distribution format from either source file, and is typically done in "the real world" to accomodate the vagaries of the marketplace. 48 or 96 k sources just don't contain enough information to produce a subjectively lossless upsample. Since the DVD Forum has seen fit to not mandate various player features that would make the consumer experience more enjoyable (persistant memory of user settings, group selection controls, complete front panel control of the player), DVD-A users have to have a TV just to listen to a title. As the “multimedia” capabilities of DVD-A, I’ve never found the slideshow feature to be compelling, especially considering the severe limitations placed on the author by the format’s limitations. Frankly, for the average consumer, there is little in the DVD-A format that isn’t already delivered more easily and more compatibly by the DVD-Video format. Badly produced audio, whether DSD or 192 k LPCM, will always sound worse than expertly and carefully produced 48k/24. Simply looking at numbers on a spec sheet tell you nothing about the intricacies of a complete media delivery system. Read a lot of information from different sources, weight your budetary options (“universal” players are now cheap but titles in both formats are overpriced) and, more importantly, listen critically before making a decision.