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Mike Rivers
 
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Default 16 bit vs 24 bit, 44.1khz vs 48 khz <-- please explain


In article writes:

24 bits also adds resolution in any region between -144 dB and full scale.


For me, with my limited understanding (or misunderstanding perhaps) of digital
theory, the above sentence cuts to the heart of the matter. If I understand
what Scott Dorsey and others have said then the change from 16 to 24 bits only
adds downward dynamic range and does not increase resolution of signals in the
relatively high ranges close to full scale.


You really have to know how to interpret this. It's easy to hear low
resolution at low levels - the limiting case is that the level is so
low that the lowest order bit never gets turned on, yet you know
there's something there. That's insufficient resolution. Go up just a
tad higher in level so that the lowest bit toggles once each cycle
(assuming a constant amplitude sine wave going in) and your sine wave
gets turned into a square wave. However, in a practical system, you'd
have to amplify by 90 dB or so in order to hear it at normal listening
volume, and we don't do that other than to show why 20 bits is better
than 16.

What having more bits allows you to do is trade off some resolution
at the top end that you won't ever hear anyway in favor of additional
working headroom. You can better deal with music with a wide dynamic
range if you have 20 dB between your nominal recording level and
maximum level than if you have only 10 or 6 dB. This is the practical
advantage to working with more bits.



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