[Radium[_4_]]

Hi:

Why is it that MP3s needs some amount of encoded audio in order to
have any audio at all, while WMA can simply make its own audio? [To
better understand this question, read below]

I have Adobe Audition 1.5 in which I do audio experiments.

Below is my first experiment:

1. I make a silent 44.1 KHz-sample-rate, 16-bit-resolution, monaural
wave file that is 4 seconds long. [To do this, go to "generate" and in
the drop-down menu click "silence". A small windows pops up giving the
number of seconds, I put it at '4']

2. I save it as "silent.wav."

3. I then convert this wave file to a 44.1-KHz-sample-rate, monaural,
20kbps WMA file -- "silent.wma."

4. I close silent.wma

5. I open silent.wma and convert it to a 44.1 KHz-sample-rate, 16-bit-
resolution, monaural wave file and save it as "silent.wav" again --
this overwrites the original "silent.wav."

6. I then close silent.wav and then re-open it. Then I convert it back
to 44.1-KHz-sample-rate, monaural, 20kbps "silent.wma" file
[overwriting the original "silent.wma"].

After generating the silent.wav file I repeat steps 2-6 at least 4
times. Now when I play silent.wma I notice audio in the file that
resembles the characteristic artifacts of WMA.

In my second experiment, I do the exact same thing, except I use MP3
instead of WMA:

1. I make a silent 44.1 KHz-sample-rate, 16-bit-resolution, monaural
wave file that is 4 seconds long. [To do this, go to "generate" and in
the drop-down menu click "silence". A small windows pops up giving the
number of seconds, I put it at '4']

2. I save it as "silent2.wav."

3. I then convert this wave file to a 44.1-KHz-sample-rate, monaural,
32kbps MP3 file -- "silent2.mp3."

4. I close silent2.mp3

5. I open silent2.mp3 and convert it to a 44.1 KHz-sample-rate, 16-bit-
resolution, monaural wave file and save it as "silent2.wav" again --
this overwrites the original "silent2.wav."

6. I then close silent2.wav and then re-open it. Then I convert it
back to 44.1-KHz-sample-rate, monaural, 32kbps "silent2.mp3" file
[overwriting the original "silent2.mp3"].

After generating the silent2.wav file I repeat steps 2-6 more than 4
times. No matter how many times I repeat 2-6, silent2.mp3 still
remains completely silent. Why is this?


Thanks,

Radium

P.S. In my post I am describing lossy WMA compression. The standard
WMA.