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The dummy head was on a camera tripod, and I had to avoid the legs, in front.
I hear it too far forward and too close when it is below. Funnily enough it goes past my feet if I listen lying on my back.

Well - the thing is, I don't hear the "below", when it's close to the vertical "body" axis. That why I asked about the distance. In my ears - it moves rather away or is undefined. What can you tell about your dummy head construction (interia)?

And - yes, it can happen, that perception is different when you are in vertical vs horizontal position; it's a sensory conflict. In this case - it probably tells about some inaccuracies in construction (external ear vs interia).

I will try this out with my head-mounted rig and see if I can achieve a sense of the vertical. I've been experimenting with Binaural the last year. I've noticed a difference in effectiveness between two exercises with movement: a "head" moving in space around stationary sounds and the environment, or, the sound moving around a head that remains stationary. The latter giving the clearest sense of localization and the former a peculiar, phasey stereo sense at worst. The best results I've gotten with binaural recordings as far as 3D perception are when the technique is used on one or some elements of a greater sound recording, mixing the binaural recordings amongst conventionally stereo or mono recorded sounds: when there is a greater context or stage the binaural recordings are set against. This track uses binaural, mono, M/S stereo, and X-Y stereo recordings placed together, variations from a single source in a single room. https://soundcloud.com/psteak/the-stomach-aches-in-the-heart

ayamahambho wrote:
Well - the thing is, I don't hear the "below", when it's close to the vertical "body" axis. That why I asked about the distance. In my ears - it moves rather away or is undefined.

Fair enough, it is a bit like that for me as well. Certainly I know that http://www.freesound.org/people/dwareing/sounds/169329/ does not work for some people.

I was aiming more for beter front/back discrimination, and better externalization when I started. The fact I was getting good vertical localization was a bonus, that I don't really understand. I never heard 'down' in many years previously. The head has no torso or legs, so that the diffraction for sounds below will be 'all wrong'. Perhaps the individual nature of pinnae will be unsurmountable after all, although I have hopes that there are enough generic simularities for it to work for most people.

What can you tell about your dummy head construction (interia)?

It is a shop display mannequin head made from vinyl and filled with foam. I have various ears made from soft vinyl through hot-melt-glue and fastcast PU, to cold cast brass, that are casts of my own. Essentially it has more than two ears/microphones, with the idea of simulating 'bone conduction' by trial and error, since its contribution is almost impossible to measure.
The files in http://www.freesound.org/people/dwareing/ use various ears, etc. They tend to have a flatter frequency responses with time, as a result of drilling holes and taking an angle grinder to it. Not something you can easily do to a real head without pain..

And - yes, it can happen, that perception is different when you are in vertical vs horizontal position; it's a sensory conflict. In this case - it probably tells about some inaccuracies in construction (external ear vs interia).

Yes, movement gives the context to localization (Pitch-Yaw-Roll); also having other reference sounds mixed in will help. Yes, sound must have enough "spectral cues" to be perceived as "localized" (that why some sounds place better in space than others), otherwise localization comes from other senses. Generally, visual feedback for example gives some percentage of localization (to certain types of sound vs distance), so when seeking for "offline solutions" - it might be good to over-emphasize some things, in order to compensate.

p.s.:
Mobile phones seem to give interesting feedback
http://www.freesound.org/people/ayamahambho/sounds/185378/
(don't listen too loud; rather emulate natural loudness).

stomachache wrote:
I will try this out with my head-mounted rig and see if I can achieve a sense of the vertical. I've been experimenting with Binaural the last year. I've noticed a difference in effectiveness between two exercises with movement: a "head" moving in space around stationary sounds and the environment, or, the sound moving around a head that remains stationary. The latter giving the clearest sense of localization and the former a peculiar, phasey stereo sense at worst. The best results I've gotten with binaural recordings as far as 3D perception are when the technique is used on one or some elements of a greater sound recording, mixing the binaural recordings amongst conventionally stereo or mono recorded sounds: when there is a greater context or stage the binaural recordings are set against. This track uses binaural, mono, M/S stereo, and X-Y stereo recordings placed together, variations from a single source in a single room. https://soundcloud.com/psteak/the-stomach-aches-in-the-heart

Agreed, totally. When I was doing some 3d sound rendering ~20 years ago.. I did a helicopter pan thing. Changing the patern of refections, so that some moved closer in time and some later in time, monotonically, added to realism. I also added some music background (Dylan) passed through the same filters, which also helped.