Does custom eartips change (significantly) the IEM frequency response ?

[oursmagenta]

Hello,

I'm wondering how much does custom eartips affect the IEM frequency response, especially regarding the eardrum to IEM driver/nozzle distance.

I think their are some discussions on the fact that the insertion distance can affect the IEM's frequency response (raised in the hot 5128 vs Gras fixture debate).

From what I understand these custom eartips are designed as an extension of the IEM, like lying on top of them. As such it seems that the cavity that goes from the nozzle of the IEM to the eardrum does not fall into the standard deviation of human anatomy, but more likely falls outside of the so to speak ODD (Operational Domain Design).

Best,

 

[Yasuo]

It changes the sound, but how much... it varies from case to case.

 

[Miley_B]

I have some silicon custom moulds that fit a generic IEM that I own.
It does change the sound significantly, but not to the point where its tuning is unrecognisable.
AB testing against the standard tips is difficult as the fit on the customs is very snug and I find silicon much harder to insert and remove than acrylic, it takes me quite some time to switch between them.

As such it seems that the cavity that goes from the nozzle of the IEM to the eardrum does not fall into the standard deviation of human anatomy, but more likely falls outside of the so to speak ODD (Operational Domain Design)

I don’t fully understand what you’re saying here. If they are custom then they will only fit the person who the mould was made from.
The custom mould boot that I have for a set of generics is very large compared to the unit when used with standard tips and significantly larger than my current go to custom mould IEMs.

 

[oursmagenta]

I have some silicon custom moulds that fit a generic IEM that I own.
It does change the sound significantly, but not to the point where its tuning is unrecognisable.
AB testing against the standard tips is difficult as the fit on the customs is very snug and I find silicon much harder to insert and remove than acrylic, it takes me quite some time to switch between them.

I don’t fully understand what you’re saying here. If they are custom then they will only fit the person who the mould was made from.
The custom mould boot that I have for a set of generics is very large compared to the unit when used with standard tips and significantly larger than my current go to custom mould IEMs.

It seems that the nozzle won't seat at the same distance from the ear canal entrance with the adapter and without an it, I may be wrong though. Maybe you're right that the distance variation it induces is less or in the same ball park number as human-to-human variation.

And yeah A/B testing seems difficult unless having one iem in each ear maybe .

 

[Curupira]

Anecdotal advice but, everyone that I know of that went this route ended up regretting not skipping these adapters and getting a CIEM from the get go. IEMs are already so unnatural sound wise (pinna reconstruction, HRTF, subjective ear canal interactions) that I feel this type of solution only adds more unnecessary complications.

 

[oursmagenta]

Anecdotal advice but, everyone that I know of that went this route ended up regretting not skipping these adapters and getting a CIEM from the get go. IEMs are already so unnatural sound wise (pinna reconstruction, HRTF, subjective ear canal interactions) that I feel this type of solution only adds more unnecessary complications.

Interesting. Now we need some kind of measurment for these IEMs with a custom mold that fit a GRAS or B&K 5128 fixture ...