A interesting audio illusion can be made by playing 8 or 10 octave notes together, then going up to the next half step and playing them again, and so on increasing pitch by a half step each tile. PLUS: The amplitudes of each note are reduced at the upper and lower ends. (A Gaussian shaped amplitude envelope works well, possibly even a linear function.) To add clarity: follow one note, say a low bass note, as it increases in pitch. It begins at the lowest volume and increases in volume until it reaches about middle C in pitch, then it starts decreasing in volume. It sounds like an increasing pitch but it always remains at mid scale - like an Escher stairway that keeps going around on itself.
I would like to make this illusion but don't have the tools. If any eager beaver wants to try this and send me an AIFF copy, it would be appreciated, but I would me satisfied if someone could point me to a free software package or two where I could do my own.
Thanks bikerbillyboy
