Shepard Scales...

I hadn't heard of these before, but I came across this article and thought it was quite interesting. A kind of sound that is perceived as always descending as though it's an infinitely long scale run going down, except it doesn't really get much lower in pitch. You'll get it when you hear it:

Cool Brain Trick: Never-ending Scales

Neat stuff! :w00t:

Uh, that didn't work for me at all.

I've heard it before, and it worked for me, when it was done quickly. When it's slow, it just sounds like a loop of one same pitch falling to a lower one.

It technically sounds more like a Risset-Glissando than a Shepard scale, since you don't hear discrete steps. But that might just be because in this example the steps are very close to each other and follow each other quickly, that it almost sounds like a glissando. Doesn't really matter though anyways.

But yeah, for me it's like for Daniel. The illusion works only sometimes, but in most cases it just sounds like a loop to me (which it is, of course). I guess it depends a lot on the finest details of the sound (particularly the dynamics) whether it works or not.

There are several computer music pieces that make use of this effect. Maybe most prominently Risset's "Computer Suite for a Little Boy", where such a falling glissando stands for the falling of the bomb over Hiroshima, and "For Ann (rising)" by James Tenney, which is based on a rising Shepard-Risset glissando.

Hmm.. It work for me at first, then it sorta becomes "loopy" (for lack of a better word).

the concept is pretty cool: utilizing a pitch that only sounds in octave overtones and eliminating everything thing else, i.e. tonality, and by controlling the frequency of the volume you essentially are hearing a cluster chord. like that piece therenody for the victims of hiroshima, forgot the composer (they use it in Children of Men at the end during the battle at the fugee camp). but i think it's cool that this natural "spectrum" of overtones we hear define tonality while hearing a single frequency with only octave overtones really creates a sense of atonality.

like that piece therenody for the victims of hiroshima, forgot the composer

right, thanks.

Here is a "demo" that worked better for me.

http://asa.aip.org/sound/cd/demo27b.au

Pretty wild.