DVD Audio
DVD audio, as the name suggests, is the digitized audio format that delivers very high fidelity audio content on a video disc. The first DVD debuted in the market in the year 2000. From the technical point of view, the audio resolution of a DVD-Audio disc is much higher than that of a standard CD audio. This is because the DVD audio delivers bit depth up to 24 bit and a sample or snapshot rate up to 192k Hz, while a CD audio delivers only 16 bit and 44.1 kHz, though the source recording in both the cases may have been done at much higher bit and sample rate.
When the two audios, i.e., the DVD and a CD are played before an ordinary listener, it is quite doubtful if he can discriminate between the audio qualities of the two formats. This may be one reason why the average customer feels reluctant to invest in new playback equipment by purchasing albums in higher audio resolution formats.
Even though it requires an audio connoisseur of ultra sensitive discrimination to critically appreciate the audio qualities of two formats, still you do not need any super aesthetic intelligence to distinguish between the data storage capacities of a DVD and a CD. Though very similar to CDs, the DVDs hold more data. A DVD can store 4.7 gigabytes of data as compared with 650 megabyte capacity of a CD. A two layer DVD can store twice that.
There are two reasons why a DVD audio standard uses extra data space.
First reason is that a larger data space dramatically increases the sampling rate and quantization levels. A DVD Audio generally uses 96,000 samples per second and 24 bits per sample. It means that there are more than twice as many samples per second and 256 times more quantization levels.
The second reason is that a DVD has six channels instead of two to create surround sound effects. In view of these two reasons the DVD-Audio has a better chance to replace the CDs.
The other reasons of the superiority of a DVD-Audio over a CD are that the former includes Pulse Code Modulation or PCM, high resolution stereo audio, multi-channel audio, lossless data compression and finally extra materials that include still images, lyrics and so on.
