Adobe Audition 1.5 permits WMA monoaural audio at 44.1 KHz sample-rate with a CBR bit-rate of 20 kbp

[Guest Radium]

Hi:

 

Adobe Audition 1.5 permits WMA monaural audio at 44.1 KHz sample-rate

with a CBR bit-rate of 20 kbps. How does it do this? How can the bit-

rate be less than the sample-rate?

 

In a monaural WMA file that is 44.1 KHz sample rate, what is the

minimum bit-rate that is mathematically-required? Can it be compressed

to a CBR of 1-bit-per-second while still retaining the 44.1 KHz sample-

rate? If so, then how? If not, then why?

 

What version of WMA does Adobe Audition 1.5 use?

 

Also, why do WMA artifacts sound different from MP3 artifacts? What is

the mechanism behind WMA compression that gives WMA its characteristic

artifacts? Or is M$ planning to keep this info top-secret?

 

I like WMA-specific audio artifacts. All non-WMA digital audio

compressions that are below 320 kbps and/or below 44.1 KHz-sample-

rate, and/or non-monaural sound like stinky human fart. Or an angry

infant foaming at the mouth.

 

Also I don't like VBR because its artifacts are not as strong as in

CBR. In VBR, the artifacts seem to be on/off, sometimes more

prominent, other times weaker.

 

The only digital audio compression I like is WMA in CBR. The sounds

resulting from this WMA compression sort of make me think of those RF

electronic telecommunication devices used in The Bourne Identity. That

movie features some really awesome devices that make those interesting

sounds - for example, when the main character is getting his hand

screened. I also associate these sounds with the electronic

telecommunication devices used by the Soviet Union. Soviet Union has

got some really psychedelic sounds in their electronics. You know,

those fancy dial-up modems tones?

 

All digital audio compression formats other than CBR WMA, stink

badly!!

 

Here are my rules for digital audio:

 

A. Whether compressed or not, the audio must be monaural and with a

sample-rate of at least 44.1 kHz.

 

B. The only compression allowed is WMA with a CBR. No other

compression format is permitted.

 

C. In its uncompressed form, the audio must have a bit-resolution of

at least 16-bit

 

D. If compression is used, then the sample-rate of the compressed and

the uncompressed version of the audio must be the same.

 

E. If compression is used, the only thing that should be decreased is

the bit-resolution. The sample-rate must remain unchanged

 

Let's say a song that was originally recorded in stereo is given to

me. The song must to be converted to mono via the following steps:

 

1. Record audio from CD [or other stereo audio source] into Wavelab,

Adobe Audition [or other audio software] into a file. For simplicity

let's call this file "Track1.wav"

 

2. Make a copy of Track1.wav and save the copy as "Track1B.wav"

 

3. Open Track1.wav and reduce the gain of its audio by 77.5%

 

4. Convert Track1.wav to monaural audio

 

5. Save Track.1

 

6. Open Track1B.wav and reduce its audio gain by 50%

 

7. Invert the phase of the left channel of Track1B.wav

 

8. Convert Track1B.wav to mono

 

9. Save Track1B.wav

 

10. Create a new stereo wave file whose bit-resolution is 16-bit and

sample rate is 44.1 kHz. For simplicity let's call this file

"untitled.wav"

 

11. Copy and paste the audio of Track1.wav into the left channel of

untitled.wav

 

12. Copy and paste the audio of Track1B.wave into the right channel of

untitled.wav

 

13. Convert untitled.wav to mono

 

14. Save untitled.wav

 

Songs that were originally-recorded in stereo need to be converted to

mono via the above 14 steps because different sounds are recorded

differently in the L and R channels. The audio that is originally

panned to the center is significantly louder than the audio whose

phase is different in the left & right channels. This is why I reduce

the loudness of non-inverted stereo audio file by 77.5% [before

converting it to mono].

 

In the stereo file whose left channel has its phase inverted, I

decrease the loudness only by 50% and then convert it to mono. Usually

-- the lead vocals, bass, and percussion are recorded identically in

both the left and right channels. The piano, chorus, guitar, and synth

pads are usually recorded differently in the left and right channel.

 

 

Thanks,

 

Radium