Subject: Auditory wheel From: "Michael H. Coen" <mhcoen@xxxxxxxx> Date: Thu, 18 Mar 2010 17:22:30 -0500 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>Hello list, We are all familiar with the notion of a visual color wheel, e.g., a continuous, circular representation of colors in some color space such as HSV. (Here's a wikipedia page with some visual examples: http://en.wikipedia.org/wiki/Color_wheel) Of course, there are many different color wheels, given that there are many different color spaces in which to model them. I'm looking for the auditory equivalent of a color wheel. Namely, a parametrized, continuous method for generating a series of sounds that form a "perceptual loop" that has no perceived gaps. I've coded a several of these, e.g., a violin morphing into a piano morphing into a clarinet, which then morphs back into a violin. They are all playing middle C and the ASDR envelopes for the generated, equal-length samples are identical. I'm doing this to measure discriminative acuity in distinguishing sounds along the auditory wheel, as part of a larger multimodal perceptual experiment. However, what I've found is that people with musical backgrounds have far greater discriminatory power in separating nearby sounds than those who have little training. There are also "unintended" clues, such as harmonic complexity, which people appear differentially sensitive to. Thus, I wonder if there is any work in creating such an auditory wheel that might be expected to reduce bias due to background and/or culture. E.g., using a heptatonic music scale may not be a good idea and sounds derived from familiar instruments are probably best avoided as well. I would like participants to be on an equal auditory footing, so to speak. I'll repeat that it is essential that there be a "loop" in the sound presentation that is not due to a simple repetition of sounds, e.g., a sine wave rising and then falling in frequency would not be useful. Any pointers, suggestions, code, etc., would be most welcome. Best, Michael Coen