changing a file from mono to stereo

[Janina Sajka]

So, that's one way to get sound to come from two speakers, but it
certainly isn't the only way, and may not even be the most
efficient way.

Whatever it says about stereo I find myself doubting. One does
not achieve stereo by copying mono to two parallel tracks. That
is simply ludricous, or at least a very bad choice of words.
Stereo is achieved by the use of at least two microphones in
order to record the same sounds from two physical perspectives
(at a minimum). The essential aspect thus achieved is a slight
difference in time and amplitude for each sound generating
device. Please note that most CDs you can buty today aren't
stereo in this srict sense. Rather, they have panned sound to a
particular location in the "field" left to right.

Neither of this is achieved by copying mono to two parallel
tracks. Far more is required to achieve a pseudo stereo from a
mono recording--though I certainly know of such work at Stanford,
for example.

So, what is sox doing? Physical modeling to achieve a pseudo
stereo, or copying one sound stream to two sound streams? I will
grant you that the sox man pages are awful.

On Mon, 6 May 2002, Cheryl Homiak wrote:

> Yeah, but it will come through both speakers. And actually, the definition that
> i sent you says that changes it to stereo.
> 
> 
> _______________________________________________
> Speakup mailing list
> Speakup at braille.uwo.ca
> http://speech.braille.uwo.ca/mailman/listinfo/speakup
> 

-- 
	
				Janina Sajka, Director
				Technology Research and Development
				Governmental Relations Group
				American Foundation for the Blind (AFB)

Email: janina at afb.net		Phone: (202) 408-8175

Chair, Accessibility SIG
Open Electronic Book Forum (OEBF)
http://www.openebook.org