Jim Frohoff wrote:
....
> Can a DSP device be programmed to simultaneously provide : ???
> - Compression - To amplify low level a bit and bring down the high-level
> - Absolute max noise limiting - To protect from further damage
> - white noise generation (2 or 3 seperate, tuneable white-noise
> generators would be desired. One way to deal with severe tinnitus is to
> "mask" the noise with white noise of matching frequencies, then use sound
> augmentation, "a-la-hearing aid" to bring the normal sound up a few db to
> make it heard. These are used long-term in an effort to retrain the ear to
> ignore the tinnitus noises.
> - multi-frequency equalization (6 band or so) - to adjust for limited
> range hearing damage.

Hi Jim,

a while back I toured the production floors of a hearing aid
manufacturer here in Switzerland (this tour was organized by the local
section of the AES, the Audio Engineering Society).

They produce devices with microscopic-sized battery-powered
A/D-DSP-D/A-Amp units (about the size of a chick pea) - unbelievable
when compared to what we are used to in pro-audio. The DSPs have a fixed
processing path (something like frequency-crossover, multiband
compressor, 5-band eq and limiter) with programmable coefficients which
should cover your points 1, 2 and 4. It is taylor programmed to your
needs at one of their distributor's lab.

They are also very active in psycho-acoustic research, and each semester
they organize, together with University of Zurich, a course in
psycho-acoustics.

The company's name is Phonak.

Regards,
Andor