Digital BW, The Print

Hi Martin,

> > What definition says what?
>
> Dynamic range: the ratio of the strongest to the weakest sound intensity
> that can be transmitted or reproduced by an audio or broadcasting system.

Well, it's not really a good definition, as it leaves the definition of
"weakest" and "strongest" ambiguous.  Which is at the heart of the
difference we have!

I am only trying to tell you where your misunderstanding here is, so please
bear with me.  The problem you are having here is you are confused by the
ambiguous definitions of "weakest" and "strongest".  Here is a better worded
definition of dynamic range:

Dynamic Range(dB) = log10(largest amplitude / smallest DISCERNABLE signal).

Note the term "discernable".  Not lowest, not weakest...but discernable.
Discernable means perceptible.  One can only perceive a signal that is
greater than noise.

"Discernable" is the exact same as noise...it is the +/- with which the
signal can be discerned...lowest, weakest and smallest are ambiguous terms.

Also, you are taking strongest to be the top number of the range.  That is
not what is meant by strongest.  A better term is largest amplitude.  Here
is an example:

You have a signal that can range from 1 to 10.  The largest amplitude of the
signal is 9, NOT 10.  Now, let's say your noise is .1 units.  That makes
your smallest discernable signal .1.  The dynamic range of this is
log10(9/.1) or ~1.9.

Now, say you have the same range from 1 to 10, but your noise is .5...  Note
you have the same range, 1 to 10, but only have the ability to measure to
within .5 units.  That gives you a smaller dynamic range, or log10(9/.5) or
~1.6.

Did that make any headway?  My 15 minutes of lucidity is over, it's been two
hours ;-)

Austin