One very interesting thing about the Audiology Online course introducing the new Infinio line and the Spheres is the discussion around 7:30 into the On Demand course video discussing what’s new in the Phonak fitting formula APD 3.0.
The presenter said Phonak got to wondering why high-quality headphones sound so good to listeners and decided to borrow the sound shaping done by Harman curves from their Sennheiser headphone line and apply it to the frequency output of their fitting algorithm. Their initial goal was to improve non-speech streaming sounds, but in playing around, they found that listeners liked the new speech sound.
So, @JordanK might remember back when I was trialing the Lumitys vs. the ReSound Omnias, I thought that the Lumitys with APD 2.0 delivered more of a jazzed-up sound, whereas the Omnias, if a soundscape was just flat and dull, left it that way. So, I would take Phonak’s New Era course to indicate that Phonak does pay attention to the psychoacoustical landscape and delivers shaped sound that sounds better than what we might hear straight. We all hear a different sound reality in different environments with different head and body shapes. We put hearing aids in our ears that try to remedy different hearing losses in differently shaped ear canals, etc. So, now that I’m into Spheric speech, I say bring on all the processing that makes the sound that finally gets to my brain sound better and clearer!
The Audiology Online course I’m referring to, from which the quote below is taken:
A beginner’s introduction to Harman curves and how they shape sound to “improve it.”
https://www.makeuseof.com/what-is-the-harman-curve
Page 4 of the New Era course transcript where the presenter discusses APD 3.0 sound-shaping:
What we wanted to do in this next step was to look at what the developers of high quality
headphones do to maximize sound quality. Because I know you’ve all heard it before. I’ve heard it
that patients get these headphones and they just love the sound quality. So how do headphone
manufacturers get there? And they use something called Harman curves.And the Harman curve is a theoretical target sound signature that is said to produce the best sound
quality that the majority of listeners prefer.So we took that idea and ran with it, and we did some research looking at implementing the
Harman curve, those targets to maybe improve upon certain sound qualities. Initially, we actually
looked at it when considering streaming sound quality. But what was actually found is that the
information that we got. So, bringing in some of the offsets of the Harman curves, we found that it
could benefit hearing aid wearers. So the result was that some of those offsets were applied to our APD 3.0 targets.So we built a prototype and we tested it. And the graph here is showing the targets for APD 3.0 and
how they differ from 2.0 for the acoustic signal. We can see that we didn’t need to adjust APD very
dramatically, but the changes have made a big impact. So depending on what the acoustics or the
coupling of the fitting is, will basically determine whether or not how big the offset is going to be. But
what we find is that for a vented or more occluding fit, we are going to have a little bit more offset
and there will be a little bit less for an open fit.Now, these offsets are applied in Infinio devices, and what we find is that patients are really, really
happy with it.So the research that kind of helped us to make this decision in implementing the offsets was
looking at patients who were wearing both the original APD 2.0 and now the APD 3.0. And they
were comparing things like overall comfort, how intrusive the background noise was, and overall preference. And as you…
