So I have been fiddling around in Phonak Target in anticipation of picking up my Marvels on Thursday and I have a question. No matter what fitting strategy I choose the Target software shows that gain has to be limited above 2500 hz or so to prevent feedback. It seems this is the case with the aids I am getting or basically any other aid I pick to have it try. Am I missing something? I am concerned these may not work for me as a result but welcome your thoughts, experts and folks who’ve been at this for a while.
My advice is to have a professional fit them and then WEAR THEM as-programmed. Your ears DO have to re-learn how to hear complex sounds.
I’m on my 6th week. Only in the last week did a lot of tizzyness resolve into overtones. If I had gone chasing that from day one I would never learn to hear holistically again.
And I have decades of experience in audio balance, often in feedback situations.
Yes, if we put the high-gain mike on/in the ear we are going to have feedback. Feedback solutions are sometimes counter-intuitive; Killion has an article where he found a fallacy in another researcher’s result. (Actually HAs are “easy”. Wear the mikes on your body and use closed-cup headphones. Worked in the 1940s.)
Fitting a new user right TO the feedback threshold, with any decent earbud, is likely to be TOO MUCH at first. 15dB more than you have heard in years is a lot.
Your HL is not exceptional. LOTS of folks like you get great benefit from professionally fitted HAs. Don’t obsess the curves. I was understanding speech better the first day. With some oddities which get better just by listening a lot, no real change of boost.
What acoustics are you using? You are nearing ear molds hearing loss, at least power domes.
If you understand Target and how it flows, you can do a good fitting. There are fundamentals you must follow to do this. Stay with the prescribed fitting at maybe a lower % prescription early on. Do not vary if you can help it.
Read as much as you can from the Target tutorials and Phonakpro on the Internet. This forum is full of information that will help you.
Good luck and have fun.
I am not trying to self fit or anything like that. I am just an engineer by trade looking at the data and trying to understand what it means. Does the fact that the software shows gain not meeting target gain due to expected feedback mean they can’t meet the needs of my loss? I know by far there’s nothing special about my hearing particularly compared to some other folks around here.
I will absolutely let my audi fit me and gI will give her extensive notes and feedback just as I have been doing with my current aids for the past 5 weeks. It’s just a concern is all. Might not bother me if it had happened gradually, but it was fairly rapid (note: by definition not sudden, and yes I did the docs and what not, all in my intro thread) and it’s all still pretty new. And today was a particularly hard hearing day for me at a work offsite. More of the same tomorrow. Just feeling a bit discouraged right now.
Sorry. My experience was a 20 year decline. A sudden drop is a different experience and I do not know what that is like. Ignore me when I don’t make sense for you.
Your curve may not be that hard up to 2kHz, and bringing that up makes a lot of speech clearer. The 2k-4k drop is hard to fit, and I am reminded every day that 4KHz is important speech. I am also learning that most speech sounds have multiple frequencies, and I can miss 2.8kHz and still get the sense by the 5.6kHz component (we both have that long level zone above the worst feedback zone). And even 6dB boost is a lot better than none.
As am engineer you know there are Goals and there is reality. And sometimes we can find a fit that is far better than doing nothing at all.
Yes, I have good and bad days. (An observation on my Marvel M30: a bad day a week after changing the battery may mean it is about to die; but I would expect that to be all-or-nothing.)
The anticipated feedback is always a lot lower then actually running the feedback test.
I ran the feedback test on mine and it allows for maximum gain on my Phonak’s.
Thanks, that’s good to know. We’ll find out tomorrow morning how it looks for me for real.
I would never discount anyone’s experience, there’s a wealth of knowledge on this forum, that’s why I am here. I appreciate all the information whether it not it’s directly applicable to me. Danger of being a want to know and understand it all I guess.
Well I won’t say too much for now since I am trying to be quick but the feedback/real ear in ear with the Marvels showed almost identical curves for feedback, gain, and target gain that the simulation in Target showed on my laptop at home. I will say my hearing is phenomenally improved compared to the prior aids I was trialling. M receivers, #2 length, power domes in both ears, NAL-NL2, operating at a few steps above 100% full prescription overall with some midrange tweaks particularly for my right ear to get me where I felt comfortable (so does that mean my hearing is still declining?). Did full real ear as well with a sound field generator gadget, never done that before, was pretty neat. Pic of that will have to wait till later as my signal here at work is not the greatest.
Glad to hear you hear an improvement!
Was UCL factored in to the fitting? They often do UCL for me, but I don’t want it to be taken into account when fitting to give maximum dynamic range even though I still have quite a bit of playground left for the compressor. There’s also the option to put in 5 dB of extra gain if the feedback test limits too much.
Just out of curiosity, did the audi mention any particular reason going with NAL-NL2 versus the proprietary prescription?
No, we haven’t even done a UCL test. I don’t think these aids are capable of reaching it as they’re currently setup, whatever it is for me. After two days I can already find some situations where they need to be louder for me.
And also no, they didn’t give me a feel for why they went with one strategy over another. I know from playing with Target on my own that NAL-NL2 gave the best chance of being within feedback threshold, and they had already been playing with my prescription/settings in the computer before I got there so they maybe came to that conclusion before the appointment.
Quick drops in the audiogram are challenging to fit because 1) hearing test is not fine-grained enough and 2) it requires quite a few adjustment channels from the aids/software (the more the better pretty much).
It might be that your audiogram doesn’t accurately represent your hearing loss between the frequencies measured. Or if you have M30’s or M50’s, it might be that there isn’t enough channels, so it can’t provide enough gain at 3 kHz for example as it would lead to too much gain at 2.5 kHz causing feedback. Or maybe both.
About 10 years ago I had hearing aids with only a few channels and they were absolutely horrible, because there was pretty much only one handle to adjust the whole drop. Ever since I’ve tried to get my hands on to the best performance level I can to get as many channels as possible.
I was also wondering if the M receiver is powerful enough for you. I guess your hearing loss in the range of the specs, but don’t know about reality. I guess the Target software recommends M receivers even for me (at least there’s the crosshair next to it, whatever that means) .
Also, one thing worth looking at might be the size of the power dome. If it’s too small and not snug, it might leak sound more than intended.
I’ve got the M90s, figured it was worth it to just get the best they offered. Though they didn’t change the levels with the channels set to the max. I believe I have the large domes as well, though they might be mediums. I haven’t pulled them off to measure, but I can confidently say they fit tighter in the left than the right (the left was initially a little uncomfortable but it’s fine now on day 3). I too was wondering if I might be getting toward the top of the M at higher freqs, but obviously we will talk at the follow-up I ha e on the 9th and see what my audi thinks. The most bothersome thing is I am running into a lot of compression when listening to music in the car. It is annoying enough that driving home yesterday I just streamed direct from my phone. Even then I would still prefer it louder but it’s still better than getting it from the car speakers.
And in doing that I was forced to wonder if any auto manufacturers ha e thought about connecting their ICE to a driver or passenger’s hearing aids to allow then to more easily enjoy what’s on offer, better hear the parking sensors, nav instructions, etc.
Sounds like the autosense might have picked a wrong program. You should probably be able to figure out from the statistics which program it chose and check out the compression/MPO settings.
It’s a tradeoff. Being cheap, I got M30. Rated 8 channels, apparently really meaning 8 handles on the boosters. Target leads you to a 3-handle screen so you can rough-out the basic shape. You click 6 or 8 to get more handles for fine fitting. The M90 runs to 20 handles.
My Aud has some skill on these handles. I watched him and compared to when I diddled 3, 10, and 27 band EQ on PA systems looking for best sound before feedback. This image is not his tuning, but you see the challenge, and he did get a very good fit for a very new user with a steep slope.
When you click a handle part of the curve is bolded. This is suggestive not literal. Sliding one band pulls adjacent bands with it. Yes, more handles lets you then go to the adjacent band and tweak it the other way to put more kink in the curve. But everything is interacting and you soon go crazy, or get such a kinked-up curve that naturalness suffers. Yes my ear is kinky 1.2k-3k, but a “complementary” kink in the EQ will not be perfect negation. If you could do a fine-scale audiogram (in practical time) you are getting smaller kinks but more of them and that may not be an improvement.
Nothing wrong with a little kink 
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