Phonak fitting range question

The published fitting range for some power models (e.g., Solana SP) indicates a minimum of 40db at all frequencies. Does that mean the minimum loss at any frequency has to be 40db, and so the aids won’t work that well for audiograms with less than 40db loss in low frequency range? (I have less than 40 below 750hz, sloping to profound at 1.5k and beyond.) Can the gain in the low frequency range be decreased/turned off to suit the audiogram? If so, why the fitting range does not begin at a lower db, like 0db for other models? In other words, what’s the real difference between 0db minimum and 40db minimum in the indicated fitting range? Does a 40db minimum pose any limitation/constraints for fitting the kind of loss I have, or is it only the maximum in the fitting range that matters?

Thanks!
Langche

Fitting ranges are a guideline to start from. What they usually mean is that if you have a loss under 40dB in those frequencies it’s possible you will hear the general noises created by the workings of a hearing aid. The more capable (in dB output terms) the hearing aid the more noise it will make just ticking over, and if you have little loss in some frequencies and a big loss in others you might find that the payoff for getting amplification in the bad frequencies is a lot of white noise. If you have a really steep slope then you normally find you have to ignore one thing or another on the fitting ranges, your audiogram is going to stick out somewhere or other.

My best recommendation is “try it and see”. I’m in a similar position because I have a big loss in the centre and a smaller loss at the outsides, so I often have to choose between lack of power in the mid-range or crazy noises in my ears. Having tried both solutions I am happier with the white noise.

The fitting range for the CORE version Naida used to have a special marking on it “Extended range for use with bassboost and Soundrecover” that outlined low losses in low frequencies with the steep slope down. The Naida S doesn’t show this audiogram in the brochure, but might show it on the Target software same as it doesn’t show on the CORE version website info but is shown in the iPFG fitting software.

I am currently trialling hearing aids where my audiogram sticks out all over the place, but so far they are working out better than the less powerful version.

Thanks very much, this is really helpful! --Langche