Carey Carlan wrote:

Jay - atldigi wrote in
:

But that's exactly my point: only the -100 component is what you've
gained. The -1 component is not rendered any better than it was
before.

Jay, as I am a person steeped in computer bits but weak on audio theory, I
ask you to explain that statement.

A 24-bit signal offers +/- 8,388,608 possible volume levels.

A 16-bit signal supports only +/- 32,768 volume levels.

Only +/- 128 levels (48 dB) of the 24-bit signal are less than the lowest
bit of the 16-bit (providing lower threshold).

The other bits provide 256 more possible levels between each of the 16-
bits' levels.

Do you disagree with any of the above? It's just math.

Is your argument that this higher precision is inaudible?


I thought this was the question we just got hammered out. I'm going to
use a "completely" unrelated analogy to illustrate a very similar
misunderstanding that should hopefully make this clear (but may just
muddle things up more). Bear with me.

----analogy----
When we're talking about SAMPLE RATE, people who don't entirely
understand digital or analog audio get the mistaken impression that
higher sample rates (more samples) will result in a better
representation of the audio due to its documentation of information
in-between samples. Those who understand how it works try to explain
that the additional information "in between the samples" consists
NOTHING other than higher-frequency information. If you were to
"subtract" the lower Fs audio from the higher Fs audio, all that would
remain would be frequencies above the Nyquist frequency of the lower
Fs. I know you understand this one.
----analogy----

Okay, so let's think about the bit depth again. Suppose you have a
loud-ass signal represented by 16 bits. If you move to 24 bits, you
are now able to "more accurately" represent that loud-ass signal
because you can represent an actual signal that falls in-between the
bits in the 16-bit system. But this additional information is NOTHING
more than low-level information. If you were to "subtract" the 16-bit
audio from the 24-bit audio, all that would remain would be a signal at
below -96dBFS.

Can you see how these are similar situations in different domains?

It's true that higher sample rates give a more accurate reproduction,
but that accuracy is nothing but higher-frequency information.

It's true that higher bit depth gives a more accurate reproduction, but
that accuracy is nothing but lower-level information.

If you want to understand this more intuitively, you should try it.
Start with a very clean 24-bit recording. make a copy of this data,
and truncate it to 16 bits. Then convert the 16-bit file back to
24-bits. You now have two 24-bit files that are identical in the top
16 bits but different in the bottom 24. One file has music down there,
the other has silence. Now create a difference file from these two
(invert one and then sum them). You now have nothing but the bottom 8
bits of the original 24-bit file. Listen to it. It probably won't
even sound like the music it came from because all the "loud" stuff is
gone. All that remains is the low-level information that was riding on
those taller waves.

I know you're asking Jay and not me, but I'm confident we both
understand the issue and he just finished explaining that he doesn't
disagree with what you wrote above, and he hasn't said that the higher
precision is inaudible. What you need to realize about Jay's statement
(which was a reference to my explanation) is that the theoretical
-100dB and -1dB signals we're talking about are *simultaneous* and are
components of a single sound that can be considered separately for the
sake of analysis in attempting to understand this question of bit
depth, dynamic range, and resolution.

Does that make things any more clear?

ulysses