Vent issue or fitting

Background: I got my first hearing aid at the beginning of this year. They sent me a CIC (not what I ordered…), had various issues like static and distortion with “louder” noises, and died a little over a month. When I was finally able to see audiologist for followup, she said it was physically a poor fit as I complained how it hurts the bottom of my ear, and they needed to remake it smaller.

Since Oticon gave me a CIC instead of the one size bigger as ordered, I figured I’d just get a IIC for a replacement if I was going to be using the smaller battery anyways.

Just got the IIC and I can’t hear certain high frequencies which wasn’t an issue to begin with; i only have low freq congenital conductive loss similar to otosclerosis. 4k and 8k is at least 20 dB worse than unaided. 6k seems fine. This didn’t happen with the one before. Looking at the hearing aid itself, the vent seems much smaller on the outside (half the size or more); the inside seems the same size at before. Is this the issue? Perhaps this is why the one before was too large; it was the vent side that was poking out and into the bottom of my ear.

This fitting experience was also very different from the first so I don’t know if that’s part of the issue. First time I spent over an hour there and this time was just 20 mins. I had to run back because it was unbearably loud despite already having it adjusted down already.

Venting affects the lows rather then the highs.

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If you Google "Phonak acoustically optimised vent " you will get a better understanding.

No, my supposed to be as large as possible vent is to allow pass through of high frequency.

As pointed out above, the venting tends to impact the effect of lower sounds more than the higher frequencies.

If the higher pitches sound weird, they can be adjusted within the software.

The bigger the vent, the more low frequency passes through, not high frequency.

@Zebras sorry I know this was a topic a few weeks back but would it be reasonable to maybe ask my audiologist to widen the sound bore in my earmolds? They are very narrow (I would say around 0.30mm?), and I do feel occlusion and my own voice is too boomy. I am guessing probably not because of how bad my HF is? But if bigger vent means low frequency can pass and not HF, then what is the problem with increasing vent size?

Hmm… everything ive read for my specific type of loss says i need the largest possible vent so that I get my natural high frequency.

My first hearing aid and my current one, were both adjusted so that I have 0 amplification in the highs (I don’t know the specific ranges) and one or two clicks on bottom. Everything sounded fuller on my previous hearing aid even though when I tested on my app, my low frequency was slightly worse before. My current one sits further in my ear, not sure if that matters.

Looking at your audiogram show’s you don’t even need a hearing aid on the right side and you don’t have any high frequencie loss? but your left needs the
low frequencies, so I don’t know where you read you need higher frequencies, you don’t need any thing there, and yes a 2-3mm vent for your left would be suitable for lower frequencies.

Vent won’t change what they do depending on shape of audiogram.

Venting affects the lows rather than the highs.

Um_Bongo is a professional with many years experience and even he says, vents effect the lows rather then the highs.

Maybe you thought - The bigger the vent, the more change of feedback at high frequencies so the hearing aid limits it’s gain due to the risk but that won’t come in to your hearing aid as you don’t have any gain at the highs.

@craftycrocheter

The smallest possible vent is actually 0.8mm which is called a pressure vent. Pressure vent helps with pressure but don’t effect how things are programmed.

You can’t get any smaller, unless no vent at all.

There’ll be a fine line of having the vent open as much as possible for your lows but not so much so, that your highs are limited with feedback issues especially as your highs are so bad.

" With reverse slope losses, we hear the highs. When we wear hearing aids, there are only two ways we can do this. One is if the ear molds have large vent holes. The second way is if the hearing aids are wide band aids (and almost none are) and amplify up to 16,000 Hz or so. (Most hearing aids only amplify up to 6,000 Hz or so.) Thus, by wearing hearing aids, we hear less than we should—unless provision is made for us to hear the high and very high frequency sounds upon which we so much depend."
from Adjusting Hearing Aids for Reverse Slope Losses Other sites describing my type of loss says the same. I can only get the most basic aid so option two is out.

Here’s what my CIC (the one I returned) looked like and my IIC (what I have right now).


The reason I’m asking is, my audiologist appointments are always 4-5 weeks out. If my mold needs to be remade, perhaps I can just drop it off without appointment. I don’t know if “make vent as large as possible” was communicated to the mfg; I stupidly assumed that everything would be copy/paste from CIC except to make it smaller.
I hope this isn’t something that’s going to take an entire year.

you can’t call your loss reverse slope in the real sense of the condition, you have near normal hearing on your left and perfect in the higher frequencies, reverse slope would need to fall outside of normal hearing at least, there’s also the dB difference between low to high, I don’t know what that threshold is, but you only need to give a little boost to those lower frequencies and nothing in the higher frequencies, so yeah a big vent to help out there.

Dude, that’s practically a textbook reverse slope loss. Agreed that it’s pretty mild, but at 30dB you’d be inclined to hear it especially WRT the great hearing on the other side.

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Making it smaller reduced the space available to fit a vent. That might be all the venting they can fit in an IIC.

Any custom device is going to occlude the high frequencies and they’ll have to be replaced electronically.

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