Does positioning of the domes in the ear canal affect REM?

I have noticed if the domes work there way out of the canal just a little, I get vibration in my voice and anyone else’s voice also. I just had an REM and I wondering if the domes were in that far when REM was done and does it even matter with the results.

I have watched Dr Cliff’s video on REM and he measures how far in to put the little tube.

Indirect way of measuring if it’s sitting at the right place is to check the response in some very high frequency, my fitter showed me and said, but I forgot the details. Point - they don’t need to pull out the measuring tool, it’s all already there. Plus the tube holder has some marks on itself already.

When I suggested to create custom molds that went deeper into the canal to prevent occlusion effects, my audiologist at the university hospital pressed me to get a separate REM measurement for those molds. Apparently, the REM values are strongly dependent on the canal volume between the ear drum and the dome.

So yes, there could be an effect due to the change of dome positiion. However, the effect is small when the change in ear canal volume is small.

Standing waves or vibrations can be diminished by changing the ear canal properties: The dome is the easiest to change. Change the size of the vent, the type of the material. If you suffer no problems with the HA in its proper position, you could try to make sure it doesn’t move. For BTE’s it is enough to slightly change the angle of the flexwires toward the head. This can be done either by changing the position of the connection to the HA in the case of flexwires or heating them with a heat gun.*


*If you want to DIY: The plastic is thermoplastic. So be conservative: Even if it takes 3 minutes to heat it, it’s better than melting!! If you have a spare wire, practice first.

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My Audi has redone the REM test even when changing the Vent size of my ear molds or ITE hearing aids. And I have always been cautioned about insureing that my aids or ear molds are all the way in the canal like they should be if I want to hear the best.

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Yes a small change in position or ear contact will change your hearing and as mentioned, that’s why the sensogram which measures the sound response in the ear and the vent effect & feedback must be redone every time a mould changes. A small position shift could give you slightly more low frequencies and less treble affecting speech comprehension, the hearing aid needs to be stable in the exact position it’s worn and that is comfortable for you, then the sensogram run. This ensures it is set up exactly right for best speech comprehension as it’s worn. It may take a few attempts to get the right ear moulds for you but this is a normal part of the process, ensure the sensogram is performed each time otherwise your hearing won’t be as good as it should be.

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I’m almost sure this is what it is. The OPN wire I’m trialing are designed different than the Widex and I have no problems with OPN’s staying in. I will consult with my audi, maybe she can heat and change the wire on moments more like the Oticon’s.

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