Fitting Range of Starkey IQ11, Phonak Smart S IX

Hearing Aids
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#1

Hi all,

I am testing for a couple of weeks both mentioned aids, at different audiologists.
I have a bias for CIC and this Starkey is such one, actually an ITC due to the size of the largest available speaker it contains.
Unfortunately, I cannot assess yet which one provides me a better speech comprehension, maybe - this is one audi’s assumption - because until now I had aids that are very weak, so I have to learn again to deal with the high frequencies I missed so far.

Could you help me estimate which model is more sufficient for me please?
Or are both too weak?
The gain curves are more or less the same. Also, whereas the Starkey’s parameters are 131 db output/71 dB gain, Phonak offers 133 db output/69 db gain (RIC with hard shell containing the Superpower receiver).
A Phonak rep tried to tweak my Smarts, but he estimated I would need probably at the latest in 1-2 years some more powerful model like the Naida S.
He showed in one of Target’s view of my audiogram that with the Smarts it’s difficult to get enough gain on some high frequencies.
Should I become reconciled to this explanation and give RIC and ITC a miss, by choosing BTE?

I have read here about a lot of interesting topics, like the “Most Powerful CIC”, where Starkey was estimated to be powerful enough for severe losses.
The audi which recommends me them is very optimistic about their adequacy for my loss. Until now, he showed me a fitting range diagram in Starkey’s fitting software according to that there is plenty of power and the aids would have even a lot of reserve in case my loss worsens later on.
This makes me suspicious. I showed him recently the substantially different fitting range diagram I found on Starkey’s homepage, that ends on the Hearing Level line of 110 dB. He at first said that’s incorrect, then later on also that the aid’s chip gets more mileage out of this situation, showing a diagram with some grey extension zone hitting the 140 dB line.
Sounds quite like humbug, or is really considerable optimization by software possible?

He lowered compression parameters, the aids are now much louder, but also distortion is ascertainable when children or women are speaking loudly. This also could be an evidence for achieving the limit in the aids’ power, isn’t it?

Nevertheless the Starkey’s clarity of sound is perhaps a bit better. The Phonak’s directionality features could help a lot, but until now these zoom features are not sufficiently helpful for me.

Thanks for your help & suggestions.
Thomas

Freq L R
0125 20 20
0250 35 30
0500 45 45
1000 60 50
2000 65 100
3000 90 85
4000 90 80
6000 80 90
8000 65 70

#2

No question, a BTE can have more brute force than a CIC, RIC or ITC. Starkey does have a very powerful IQ based BTE I saw in Vegas this year. But it doesn’t look like you are a candidate for something so powerful.

I can’t imagine why you would need to be wearing anything more powerful than 71dB of gain right now, or for the foreseeable future.

#3

ZCT, please explain this more fully for us newbies. According to their signature, I believe the customer’s worst heariing is 100 dB down from the normal of 0dB.

How does that translate into only 71dB of gain needed. Shouldn’t that be 100dB ? (plus more to allow for future loss)

I am not questioning your expertise, just trying to learn.

#4

No problem, I’ll try to explain. First off, there are more than one decibel scale out there. Hearing is tested in dBHL, which is designed so that normal hearing looks like a horizontal straight line along the top (0 dBHL). Most other references to decibel are actually referring to dBSPL (sound pressure level); a different scale entirely.

Gain is a measure of the ratio of input to output, and so it doesn’t follow that a 100dBHL loss needs 100dB of gain to assist it.

In fact in 1944 Lybarger did studies and concluded that on average it was found that patients only needed half the gain of their loss. Such that a 50dBHL flat hearing loss would actually only need 25dB of gain.

Modern fitting formulas are often far more complex than this, and take a lot of factors into account. But as a rule of thumb if you want to have a rough idea of gain, look at the average loss at 500 / 1000 / 2000 and half it, and that’s about how much gain you should need give or take.

#5

Is the limiting factors for many of us is recruitment for usable need for amplification, etc.?

#6

It can be. But even someone with no recruitment isn’t going to need gain equal to their loss.

But you are referring to dynamic range. Take the threshold results, then take the UCL results. This represents the quietest sounds you can hear, to the loudest sounds you can tolerate. Then look at the MCL results; the sound that a patient finds most comfortable.

The goal of a hearing aid is to play close to the MCL, while never making a sound quieter than the threshold (because a patient wouldn’t hear it), and never playing a sound louder than the UCL (because a patient would find this unbearable).

Bottom line; to achieve this desirable outcome requires far less gain than 1dB for every 1dB of loss.

#7

Thank you, ZCT. I’m glad to know there are more professionals that subscribe to this view.
It’s quite confusing for the amateur to hear so heavily contrary opinions.
My loss is considered to be severe (or profound?), and even 10 years ago when it was milder on high frequencies I found only one audi willing to fit CICs for me.
Now it would be frustrating to experience the same even with RICs.

The Phonak rep’s explication was that the gain RICs provide on low frequencies is sufficient, but there are only two manufacturers of receivers for all brands of aids, and until now the small receivers of RICs or ITCs can not provide much gain on high frequencies because that would require the receiver to pulsate stronger. BTEs have larger receiver surface, facilitating huge pulsations.
And we all need high frequencies for speech comprehension.

Is there any rule of thumb that recommends some basics, like BTE for every loss worse than x dB on y frequencies?

ZCT, can the multi memory button on the Starkey CIC/ITC also be added on, or can it be ordered only at the outset? Additional costs?
The feedback management is efficient, but still restricts frequency output, could it make sense to tamp the vent?

BTW, good news for those who may give Spice a try: the Phonak guy said he installed a new version of the feedback manager, saving 6 dB of the gain the previous version has cut.
Also, in my first fitting sessions whistle could only be stopped by badly cutting gain, until the audi found and installed a new version of the firmware.

#8

I can’t really refute the Phonak rep’s opinion, since like Chinese whispers, I feel it may not be precisely what he was trying to say.

I would argue that RICs are better at HF gain, and BTEs are generally better at overall power.

I don’t want to sound all Cris Angel here, but there are a number of factors that one takes into account as a hearing professional, and often I will test my theories with test aids to see how the patient responds and how much gain they like. On difficult cases I might have my patient listen to a RIC and then a BTE and compare and contrast. I’ll be monitoring what gain they like, and what kind of sound they are most comfortable with. I’ll be looking for feedback issues, and overall hearing ability.

Based on a series of tests involving real hearing aids, I’ll make my recommendation. Some of this is gut feel, experience, and science. It’s a number of things, and there are no hard and fast rules because one person might like one thing and another with a similar loss may have very different needs and wants.

I think the concept of adding a multi memory will come down to age of the aid and willingness of the factory to do a favor for the hearing professional asking for it. I’ve had situations where the lab has done things for me as a favor based on my long term relationship with them. So again I don’t know what the official ruling is on this. I do know it is not especially easy and is going to incur some cost at the lab end. So how much they pass on to the hearing professional and thus the patient is going to be case specific.