[Harry Rossman] offered the fact that he would "continue to be bothered" by the general consensus from the profession’s academia, which is absorbed as absolute a heavenly truth, that electro-acoustic analysis of a number of “acceptable” target prescriptive algorithms, developed by significant labs worldwide, were actually valid predictors of success with a hearing aid.

Not so, he allowed, the ear being akin to matching a receiver to a transmitter in a radio, for one example, wherein it would be tuned just below, then above, and finally landing on the “sweet spot” where the signal was clearest. This, of course, would require the shocking realization of academia that the human ear and hearing must be treated as a research project with a sample space of one, or unique in each situation and each individual, evaluated within the dynamic range and frequency response of their hearing in response to the signal which they want to hear the most: live or recorded human speech. Of course, this would preclude electroacoustic evaluation as an end in itself and view it as being far down-line from the true end-product of the production line of audio-prosthetic hearing correction. There were reasons I agreed.

One was that this is exactly the way I have been thinking since graduate study, in increasingly honed and modified test technique (which had the heretic nature of being original), in which, by use of master hearing aid, and a paired-comparison tournament technique, the exact point on the sound pressure continuum of loudness and pitch was measured for the average voice in each individual ear and the balance effect thereof in each individual’s binaural hearing, for the optimal response in both comfort and clarity of human speech.

I brought this very point up at an Academy of Rehabilitative Audiology conference in the mid-'90s, and in a submission for original research at the charter Biennial Hearing Aid Research and Development Conference [now known as IHCON], sponsored by the Veteran’s Administration, National Institute of Deafness and Communicative Disorders, and National Institutes of Health. A method for accomplishing the above means was accepted for poster presentation. Peer review personnel for this conference were nationally recognized experts but with a more tolerant acceptance of innovation and creativity. (To me, this still remains the best conference on hearing aid research in America.)

The presentation was of a copyrighted audiotape of a formal procedure that we use to find the “sweet spot” of human hearing , which is then validated in various forms of computer or CD/taped version of real-life background noise, both the speech signal and the noise being measured for the varying signal-to-noise ratios and distances. This requires a master hearing aid and, if more creativity is to be allowed, a custom built, full-room size test-suite [like the one we’ve built] with various noise sources geared to replicate real life, emanating either from the walls, ceiling or test-equipment, as necessary.

By concentrating on evaluating the psychoacoustics versus the electroacoustics—though neither ours or any other system has received the “Perfection Award” yet— we have achieved a quite credible and low return-rate and, according to customer surveys, an acceptable customer satisfaction rating.

As clear a speech reproducibility as possible: that’s our goal so our patients can hear what they’ve been missing!