damien907 wrote:from wikipedia:
24-bit digital audio has a theoretical maximum SNR of 144 dB, compared to 96 dB for 16-bit; however, as of 2007 digital audio converter technology is limited to a SNR of about 124 dB (21-bit)[12] because of real-world limitations in integrated circuit design
^^^is that real world limitation thing what your talking about?
Yes, you don't get the full 144dB/24 bits of dynamic range.
damien907 wrote:i was always taught that dvd's have more dynamic range because of the bit depth in their mixes. the signal to noise ratio is way higher in 24 bit audio than it is in 16 bit audio. what im trying to get at is, because of this, for all practicality, a dvd will usually always have more dynamic range than a cd by design because its 24 bits...wont it?
The audio component of a DVD-Video can be generated from 16 bit, 20 bit, or 24 bit sources, it is not exclusively 24 bit.
If the audio on a DVD-Video is made from 20 or 24 bit sources, then it can theoretically have more dynamic range in the signal stored on the CD.
Generally though, if you are comparing differences in dynamic range between the audio on a DVD-Video, possibly a movie, and the audio on a commercially released music CD, then you will most likely be hearing differences in the mixing and mastering of the audio based on the context of that audio (movie vs music), rather than differences in the dynamic range of the format (DVD-Video vs CD).
At least in relation to movies on DVD-Video, the audio is generally mixed and mastered leaving a lot of dynamic range, from the quietest sound/whisper, to the loudest explosion, there often needs to be, or it results in, a large dynamic range.
With a commercially released music CD, it is generally mixed and mastered using compression, limiting, and brick-wall limiting, in an attempt to be as 'loud' as all the other commercially released music CDs, which results in a greatly reduced dynamic range compared to what is possible on the format.