I want to see music

July 27, 2011 9:13 AM

Is there any relatively agreed-upon audio visualization standard, or are all visualizations of audio just interpretations of the sounds?

When I was a kid, my dad had a stereo that included a little green line in a big glowing square. The line erupted into peaks and valleys in time with the music...with low tones showing up as activity on the left-hand side of the box, and high tones show up as activity on the right-hand side. The louder the tones, the higher the peak.

Was this just a gimmick on his stereo? Or did it--and other, similar types of audio visualization--depict something actually objective about the music that could be interpreted if you were only looking at the visualization and not hearing the sound it represents?

Is there any objective visualization of music apart from notation?

posted by jefficator to media & arts (5 answers total)

That was a spectrum analyzer. It's one of two standards. (The other is an oscilloscope trace.)

A lot of equalizers include spectrum analyzers, though they're usually displayed using lines of LEDs rather than using a display tube.
posted by Chocolate Pickle at 9:24 AM on July 27, 2011

Chocolate Pickle's got it, as far as standard visualizations go. I'd point out, though, that some less-sophisticated systems, usually looking something like this, have displays that resemble spectrum analyzers but actually just respond to overall volume — or, in the worst case, to nothing at all, simply displaying a random pattern. Something to keep in mind if you notice visualizations "in the wild" now.
posted by hatta at 9:37 AM on July 27, 2011

Film optical sound tracks are representations of sound that you can see. Those sounds might just be music and then you could see them. http://en.wikipedia.org/wiki/Sound-on-film
posted by bdc34 at 9:40 AM on July 27, 2011

A spectrum analyzer with enough resolution can have enough information to objectively represent the music exactly, i.e., you could in theory capture the output of the spectrum analyzer, do a reverse Fourier transform on it, and get the input signal back.
posted by zsazsa at 9:47 AM on July 27, 2011 [1 favorite]

Oh, and a spectrogram, which is essentially the output of a spectrum analyzer plotted along a time axis, has been used by some artists to hide pictures in their music.
posted by zsazsa at 11:23 AM on July 27, 2011