CD has now been around for a good few years and is being challenged by the new SACD and DVD audio, both of these new formats claim significant improvements in audio quality, extended playing times and true surround sound. Their appearance in the market place has confused a significant number of the buying public.
Both new formats suffer from a serious lack of available repertoire and this is not likely to improve in the next year or so, if the record companies restrict their new format output to genuine 24 bit original masters then it will take a very long time to equal the existing repertoire.
DVD audio is mainly backed by the US. and is an extension to DVD video, it uses a shorter wavelength laser than CD. At present the discs can only be played on dedicated DVD audio players, first reviews of these players suggest that replay quality is not as good as a medium priced CD player. Additionally the DVD players usually require a tedious navigation through several menus to achieve the correct playback mode.ie. stereo or mulichannel or with pictures, this means that you cannot simply load a disc into the machine and press play as you can with a CD player.
It is possible to play CDs in most of the DVD players but it has been noted in a number of reviews that the overall quality seldom reaches the level equal to that of a medium priced CD player.
SACD is backed by Philips/Sony who co-developed the original CD standard, like DVD a red laser is used to allow for the extra data storage. although a SACD will only play on a dedicated machine it is planned to issue most discs as dual layer format allowing automatic playback (in 16 bit) on any standard player. When playedback on an SACD machine the user will be required to choose standard stereo or multichannel surround sound.
Reviews suggest that very good quality can be obtained from a good SACD machine, though the discs are very expensive to buy. It is expected that the price of all machines will fall significantly over the next year.
It would be a sensible conclusion to stay with CD for the foreseeable future, although it is claimed that new systems are much better because they offer 24 bit at a higher sampling rate, this is very difficult to justify. After all, the present CD 16 bit standard will provide a dynamic range of over 90db. It is doubtful whether a microphone exists to capture an original signal of that level without contributing noise above that level.
Modern mid priced CD players are now capable of effective bit up sampling to extend the 16 bit code to 24 bit, and although this will not in any way increase the true overall information it will dramatically lower distortion and noise. It is difficult to imagine that SACD/DVD discs will in practice provide any practical improvement over the existing 16 bit players. It is also very unlikely that many discs will be manufactured to a genuine 24 bit standard.
It seems that the most sensible way forward for most people will be to exploit such programmes as wavecor to maximize the quality of their existing vinyl collections and transfer to CDR. When played back on a reasonable machine the quality will be very good and they will be listening to performances ( of tempo and dynamics) the like of which are not present in the repertoire of the major record labels today.
Ganymede Test & Measurement
4th July 2001