Pressure vent vs. no vent earmolds - any differences?

Are there any benefits to no-vent versus pressure-vent fittings if occlusion is not a concern?

I heard (maybe wrongly) that no-vent fittings reportedly have the drawback of creating a vacuum in the ear canal during insertion of the cShell, thus limiting eardrum vibration and reducing audibility.

Does the no-vent option make adjusting low-frequency handles easier in, for example, Phonak Target software, i.e., more independently in relation to neighboring handles?

I think also that a no-vent design creates more space for the receiver, making deeper placement of the earmold possible, which could results better sound quality.

As ever: it depends.

If there’s absolutely no slit venting and the canal is excessively plugged so that it can’t equalise, then a pressure vent is necessary/benficial. If there’s a bit of movement around the vent then it’s not such an issue.

Personally I think that v-slot venting is a little underused even if it’s just partial mould depth, it can be really helpful for power losses. Plus it has the added benefit of being really easy to keep clean, whereas pressure vents invariably block unless you’re pretty meticulous with the fine cleaning wire and alcohol spray-brush.

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If I close the vents in my earmoulds, the sound becomes like through a wall.

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But with occlusive fitting you’d need to reprogram for this, it probably wouldn’t be as bad, your original programming is for vented molds.

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:arrow_down:

@tenkan, you mean (as a rule of thumb of course) reprogramming like “low frequencies down, high frequencies up”?

From my limited experience with my DIY’ing.

After any coupling change you MUST do a complete reprogramming !

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What v-slot venting is? I googled and copiloted it, but didn’t find it.

I have a 1 mm vent in skeleton earmold for my Paradise and didn’t have much problem with cerumen. After buying a plastic wire, the issue is even easier to manage.
However that acrylic earmold isn’t ideal:

  1. is quite loose (but without falling off)
  2. I found the sound quality is much better when I push it a bit deeper and keep my finger there (without occluding the vent).

So you suggest that, in case of no slit leaks, pressure venting is better than no venting?

Yes whenever the acoustics are changed you should recalculate the fitting, feedback etc

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A slot vent is a narrow channel in the outside face of the mould.

Yes a pressure vent is better than no vent if the seal of the aid is too good.

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Allright, I am a bit surprised that this (diameter 0.6-0.8mm) could make a difference regarding that pressure-vent is reportedly considered as closed fitting. I mean, for clarification, that differences between no-vent vs. pressure vent is negligible to make clinical, real-word/ear difference.

Okay, so it’s quite similar to slit leaks, except slot-venting is a controlled “leak”.

Thanks for the clarification; it is because I recently received new mold with unwanted AOV, and must send my new mold to be remade. Hence my doubts between no-vent vs. pressure vent.

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Doesn’t really matter, your right tho, you may not notice any real world difference.

You don’t choose the types you want to use? As in you just let the audiologist work it out which would be better for you, the thing is its costing you some money to trial these different set ups no doubt, my local now wants $100 each mold.

You may be right, but for me, it almost always ends with choosing by them a bigger vent, like an AOV or 3 mm(!), because of my good low-frequency hearing and the resulting assumption that I would have occlusion, which is untrue.

In the past, when my knowledge of fitting was zero, I bought Dynamic FM SmartLink+, which made no difference to HA, because no one said it could be too large a vent, making it harder to get benefits.

For example, a month ago I ordered an earmold and clearly requested a pressure vent, because with my previous molds I couldn’t reach targets above 1-1.5 kHz… I received cShell with AOV, aaargh…!
Indeed, it’s reasonable ~$100 equivalent for one titanium cShell, but still…

Below my feedback threhold with described cShell with AOV (no-REM)…

NAL-NL2 in non-REM, full-believing-in-app adjusting is simply too quiet for me, probably because of not reaching a threshold?

Just my personal experience.

I hear better with vents. The unvented domes seemed to make everything sound muddier by suppressing high frequencies. BTW, I’m a musician, and my ears are trained to listen to frequencies.

However… Did you have any adjustments after changing to unvented domes? It seem you simply didn’t have readjusted gain for high frequencies.

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Yes. The audio made the adjustments along with another ear test.

But it stands to reason, if the outer ear is sealed, the eardrum would not be able to move as freely.

I currently have vented ear molds, and they are the best I’ve had so far.

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Alright, thanks for reassuring me. I’ll take my cShell for remaking on Monday.

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