"Mike Rivers" wrote in message
news:znr1069010813k@trad
In article
writes:

So what has happened? Yes, we have increased out dynamic range by 6
dB between the loudest and softest signals the system can represent.
But we have increased the resolution throughout the system: from a
6dB increment to a 4 dB increment.

Continuing to a 3 bit system: dynamic range is 18 dB. Values are 0dB,
2.25 dB, 4.5 dB, etc. to 18 dB. Wth each additional bit the dynamic
range is increasing, but ALSO the resolution is increasing
everywhere in the system.

So your next question should be: "What do I HEAR that's different?"

A good way to answer that question is to listen to some very low bit
rate recordings. I know this sounds like blasphemy, but once you get
up to about 8 bits, you don't get the sense that you're increasing
resolution, you get the sense that you're reducing the background
noise level into which the signal disappears.

This is clearly audible in a series of samples, originally recorded by Ethan
Winer, that people can download from http://www.pcavtech.com/test_data His
article is good background reading and can be found at
http://www.ethanwiner.com/BitsTest.html .

So yes, your ears are
able to RESOLVE a lower level signal in the presence of noise because
the resolution down there is better.

However, on the practical side, since most of the music we listen to
today has a dynamic range of less than 10 dB and is played back well
above the system and ambient noise floor, you don't get much of a
chance to take advantage of the added resolution. Of course it doesn't
hurt to have it there (for the occasions where you actually can use
it) but I'll bet you could sell 8-bit pop music CDs today and nobody
would complain about the sound quality.

Sad but true. Only I'd raise the bar to about 10 bits. People can listen to
the files at http://www.pcavtech.com/test_data and reach their own
conclusions.