On 2011-11-27, Eric Carmichel wrote:
My current research interests include cochlear implants and the possibility of creating “real-world” virtual listening environments for studying hearing aid and cochlear implant efficacy in a variety of noisy and moderately quiet environments. I see the potential of Ambisonics as a research tool for my research and hearing scientists in general; [...]
Time for a little bit of ambisonic heresy, I think... While ambisonic is really good at recreating full soundfields, it resorts to some psychoacoustic trickery on the way. As I've understood it, hearing aids and cochlear implants then have some of their own built in as well. As such, what you're recreating when you use a -- low order -- ambisonic system will lead to a soundfield which sounds right to a normal ear, but still has all sorts of out-of-phase components and directional smoothing which might throw off the algorithms within an implant's driver.
Thus, I'm guessing ambisonic will be highly useful for testing reverberant spaces and the like. But it might prove less than reliable as a substitute for live testing in the case of point sources and in particular speech, which I understand most sophisticated hearing aids are now optimized for. Thus, I'd seriously consider validating your results with physical point sources in those cases, and if you want to play around with those within a recorded ambisonic field, to apply something like DirAC-preprocessing even if you rely on ambisonically recorded material. (I'm certain Ville Pulkki of TKK/Aalto University would be more than happy to help you with that sort of thing, if you decide to go there.)
-- Sampo Syreeni, aka decoy - de...@iki.fi, http://decoy.iki.fi/front +358-50-5756111, 025E D175 ABE5 027C 9494 EEB0 E090 8BA9 0509 85C2 _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
