Re: Auditory wheel

Now I start to think about it is clear that timbre perception is our capacity to recognize how a sound is generated and through which filters it comes to our ear. In the good old days of the Institute for Perception Research in Eindhoven we had a demonstrator of the "klinker driehoek" (vowel triangle). This triangle lays in the x-y plane of which the two dimensions are the first two formants of vowels. In this triangle you can of course draw a wheel. The demonstrator was implemented on 80 by 80 cm x - y plotter that you could move by hand with a knob at the crossing of the two arms. With some exercise you could speak with it and make sentences like " I owe you ". To day you could easily implement it wit a touch screen and software like max/msp or ableton live. I think this is a fully parametrized space. Bye from Bogota.
```iPod

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On 18 Mar 2010, at 17:22, "Michael H. Coen" <mhcoen@xxxxxxxxxxxxx> wrote:
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```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
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
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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
```