I think the idea is that ReSound (same as Phonak Autosense) has programmed the mics to behave a certain way under certain noise conditions and doesn’t leave a lot of choice to the user or fitter as to how they behave.
The full transcript from ReSound’s initial ReSound One presentation is available from Audiology Online and a discussion of microphone performance and how it changes begins on about page 7 (a quote):
Again, it’s our philosophy. It’s part of that organic Hearing philosophy, we
don’t we want, we want the users of our hearing aids to get exactly the same situation
than a normal hearing person gives. And that is they hear everything around them, but
they are able to still then hear in noise. In ReSound ONE, we have improved the
directionality by now having a new four microphone beam former. So when you think
about these hearing aids, there’s actually six microphones on, the hearing aid set. So if
you have a binomial fitting, there are six microphones. There’s the <M&RIE> microphone
in the ear, and then there are the two microphones that you’re used to having that have
been there all the time. We’re using the M&RIE microphone for more quieter or less
noisy, just smaller amounts of noise. And then when noise gets you know higher 60, 70
dB SPL of noise, then we switch into All Access Directionality. And we very gradually
move that M&RIE response up to the microphones that are above the ears, and then
we use the microphones above the ears to create the directional response.
I didn’t try rereading the whole presentation but I get the idea from skimming through now and memory of previous ReSound presentation on the Quattro’s that different sets of mics may be doing different things for the user, e.g., all 6 mics are not focused on one thing but mics in one ear might be concentrate on speech in front of you (because it’s closer and less noisy on that side) whereas the mics on the other side might be doing something else, focusing more on noise and suppressing it, because it’s closer) - I’m ~making this up as a “this is kinda what I recall” example.
Slides used in presentation:
ReSound courses that you can register for and audit for free, including how to use fitting software to fit ReSound One’s, etc. :Audiology CEUs | All Courses | AudiologyOnline