It’s about 1ohm OI. The drivers are 32ohm, so there is no chance its the impedance somehow.
The nominal impedance is 32 ohm, it can be wildly different at specific freqs. Can you measure an impedance vs freq? You can do it in REW but you need some resistors.
A quick test might be worth it if you have something that’s like 0.1 ohm OI that you could swap to to see if you get the same behavior (topping etc).
That’s just to get more understanding though, then it still has to be fixed 
is this a single DD? Those tend to have a flat imp curve anyway so OI wont have any effect on that anyway.
I get what you are thinking but no its not that. It’s the insane acoustics I have going on within the shell. the pressure wave from bass (front driver) gets routed to the rear chamber where the more spl pressure, the more the effect happens (for the worst sadly).
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Yes one DD only.
Tried stuffing some shell damping inside? Like cotton.
Indeed, stuffed back shell with foam. Doesn’t help.
Thats actually something I have NEVER seen in any chifi (or any iem…) I really do wonder why…
But rip, tried shell mass loading?
Yeah me either. On the one hand I was trying to do something never done before, on the other, it was opposite what I wanted to happen. #FAIL
I’ll go back and see if I can figure out how to make the reverse.
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hmm, it shouldnt have been due to the shell damping? That one shouldnt have been a fail.
Well no that works fine. It’s the fact I have the front and rear air volumes connected together… There might be a total volume that works better, so im trying some things before scrapping the idea.
do you have any damping inside the front/rear tunnel?
just a front nozzle damper, I won’t use foam or similar… regardless, I have a very nice tuning, I just need it to not change when hiking volume
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Do you know at what volumes those graphs are measured at? Like if that was measured at like 100+db and this effect only happens there but not at like 60-90db range, then maybe its fine?
Even at like 84db its doing it enough to piss me off. Gotta fix it.
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aa ok yeah.
But on the other hand, this is imo quite the unique feature, what about having a version where this is still present? (“its a feature not a bug” lol)
No way hahaha. Basically it ‘shouts’ as you turn up volume. Exactly not what I want to happen.
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see if you can make it align with equal loudness curve properly and maybe then have a version with that fixed one and one without this at all?
I gotta think about this before going any further. I refuse to just make a normal IEM… lol
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