Fitting settings for no-response areas of audio spectrum

digital_dreamer · April 25, 2022, 4:48pm

My question is how fitting software treats the areas of the audiogram where there is no response at all. If you look at my audiogram, you’ll see I have no practical response from 1.5kHz and up.
Naturally, there’s no point having an aid wasting energy amplifying this portion of the spectrum, not to mention the added damage it may be doing to the physical ear trying to send 120-130 db sound waves.

I’ve used iPFG on an old Phonak V series UP aid. It looked like it was trying to amplify that area — something that made me uncomfortable. But, I kept it as is, as I didn’t know how to get around it. I was afraid if I treated that area as “normal hearing,” it would confuse the software or create distortion.

Now, I just bought a pair of Phonak Naida B UP and have Target 7.3 ready to go. I haven’t played with the software much, yet, but would like some suggestions regarding how this should be treated. Does the software automatically take care of this, knowing this is a null area and there shouldn’t be any amplification here?
Also, I wonder how SoundRecover 2 handles this.

Thanks for any input.

pvc · April 25, 2022, 5:19pm

Phonak Target has a Pulldown Selector to the right of “New Session”. You can pull it down and select “New Training Session”. These simulations might help you to get a feel for how the software works.

Maybe create a dummy test client, click some points on the left audiogram, copy the points to the other/right side, change the other/right side to have some No Response points using right button click. Proceed into fitting and compare gain on the two sides.

I think it will add gain for the NR points. Probably up to, but not over the Max.

david.hendon · April 26, 2022, 2:37pm

I’m sure that is right.

Although there may be no response to the threshold test, the may be a response at higher levels that one meets in practice and anyway sound isn’t pure tones and if you cut out all the high frequencies, it will alter the time response, which could reduce the residual intelligibility.

But if someone wants to lower the output at frequencies that are considered dead, then just lowering the relevant gain handles 10 dB or so will do that. But I suggest not to do that all the way down to 1.5 kHz. Maybe stop at 4 kHz or 3 KHz so the cochlea gets some high frequencies.

digital_dreamer · April 28, 2022, 3:50pm

Good points, all. Thanks for your valuable input. Much appreciated.

Zebras · April 30, 2022, 6:45pm

@digital_dreamer

I actually tested this theory out with my friends audiogram.

Selecting NR at a certain frequency actually increasing the gain massively.

That’s with just entering all of his details in (including audiogram) but not actually connecting the Aids but I’m sure it’s the same.

cleveto · May 6, 2022, 12:06pm

A little input from one (or more) of the Registered Providers may help enlighten everyone on this.

pvc · May 6, 2022, 1:03pm

Our very knowledgeable Registered Providers don’t generally peruse this semi-hidden DIY category.

Zebras · May 6, 2022, 1:19pm

As we are DIY, why don’t you just see what happens when you select a frequency as No Response?

That’s what I did on the Phonak Target software, I didn’t need to connect the Aids or save the session once I figured it out!

digital_dreamer · May 10, 2022, 3:11pm

Yep, there’s massive gain there for the NR areas. Scary stuff. Plus, I have the High MPO warning where “one of more programs exceeds 132 dB (ear simulator).”

My problem with this calculation is that it appears the program is assuming SoundRecover can work in the NP areas. Is that not what it looks like? Why concentrate on those NP areas? I need, or would like, the NP frequencies to move down (and compress) into my audible range (within reason). Of course, some distortion is expected.

I have BassBoost on high, BTW.
This is preliminary:

david.hendon · May 10, 2022, 4:50pm

Sound recover moves the input signals down into your audible range, not the output signals. So whether you are NR or not at the frequencies that sound recover is working on is irrelevant. It will still move them down into the range you select for sound recover in the fitting software.

digital_dreamer · May 12, 2022, 8:16pm

Alrighty. I’ve adjusted the GAIN LEVEL in Global Tuning to 80% target gain (70% was a tad too low). That dropped down those high frequencies and brought the low end up.

In SoundRecover, I’ve shifted the cutoffs down the spectrum - Audibility is set at #1

I’ve loving what I’m hearing. So many sounds I’ve not heard are audible.
I can hear the microwave beeps and the seatbelt alarm. I’ve rarely heard them before, but they were so “high pitched” for me. Now, they are lower frequencies that are very noticeable.

At work, I can hear the beeps from our high-speed impact printers, something I’ve never heard before. I was working on our $70,000 Computer to Plate imager, adjusting the voltages levels on the power supply, as we were having issues during the sudden hot whether and humidity (A/C isn’t working well). For the first time, I could hear the 24-volt alarm that happens when you take the cover off. Before, I had to view the LCD display for this alarm. Now, I can hear it very distinctly.

Not only that, everything still sounds “natural” (for me) and not annoying. It was irritating the first 3 days until I got it tweaked where it was workable.

I’m using the iCube II for programming and the ComPilot II for streaming.

Target Gain at 80%

SoundRecover2 set at Audibility 1

Our ECRM Mako News System CTP for printing plates: Can hear the warning beeps!

david.hendon · May 13, 2022, 5:38am

It’s fantastic when something works out so well like that. Well done!