Does a new mold require another REM or just a new feedback test?

[DaveUK]

I am trialling KS10s with cShell earmolds. Unfortunately, the mold slowly but surely moves away from the eardrum (probably as a result of the ear sweating and the aid slipping). This has a significant impact on speech recognition (it gets much worse). My previous aid are Phonak Virto Q90s with half shells. The VQ90 half shells fit perfectly.

Costco HIF has requested new cShells and I have provided him with the serial numbers of the Phonak VQ90s so hopefully they can get the same fit. Costco will send me the new cShells to my home address and I will connect them myself (I am happy to do this as I self-program). I have a follow-up appointment a couple of weeks after they are due to be delivered to me.

I will do the feedback test (I have the Noahlink Wireless and Target 7.1.9 to do this). But my question is whether REM needs to be re-run with the new cShells (which I obviously can’t do myself). If so, I will ask the HIF when I see him.

[Raudrive]

I will throw my thoughts in on this.
REM is great but not always.
In-Situ fittings can be just as good, maybe better.

Anytime acoustics are changed real ear, feedback manager needs to be ran.

[Volusiano]

If it’s a replacement cShell that’s exactly the same as the previous one, except that hopefully this one doesn’t slide out as easily as the other one, AND if REM was done on the original cShell when it was seated properly in your ear (like this new one hopefully will) and had not slid out, then I would say that doing REM again is not critical.

But if the original cShell not only just slid out after a while, but is also a loose fit to begin with, even when pushed against your ear canal, then the old REM might have factored in the leak due to the loose fit. In which case REM should probably be done again to factor in the new tight fit.

[DaveUK]

The vent in the old HA is larger than the vent in the new cShell and larger at the tip (see photos). I reckon the old half shell is closer to the eardrum than the new cShell. So if they do as requested (make the new cShell same as the ITE), the acoustics would be slightly different.

Having said that, I suspect (hope) that REM will have given me a good approximation to a good fitting, one that is sufficiently good for me to tweak to improve to the level of intelligibility I get with the VQ90s.

[Zebras]

@DaveUK

I got ear moulds (Altho not a C Shell) that has longer ear canal length and the sound is massively better.

[DaveUK]

That’s good to know and is exactly my experience too. Hopefully CostCo/Phonak can sort this out.