Updated Earfun Free Pro EQ for various resonance frequencies (Patreon)

I had to update my EQ for the latest 2 Earfun Free Pro units that I bought recently. I assume most current units should be more or less like that. Unfortunately there is always some sample variation involved, thus everyone would need to fine tune his particular unit on his own as they will all sound slightly different. I had based my original tuning on the first early units that I got, therefore for the new units I had to reduce bass even more adjusting treble a bit at the same time and I also had to reduce the 6500Hz peak to -12.99dB for a smoother response. It would seem as if the app indeed accepted that setting although +/-12dB is usually the maximum range, I could verify with some measurements that the value of -12.99 is really saved within the device, just by recalling the setting again afterwards it may default to -12dB again.

I also created 2 additional EQs for people who do not hear the main resonance at 6500Hz or close to this. 

Here the new settings which sound better to me with the recent units optimised for a resonance frequency of 6500Hz. You may try if this sounds better to you than my pervious version, although the difference may be minimal:

Next is a setting optimised for those who hear the peak at 7000Hz or close to this. For me this setting sounds off and I hear a distinct resonance, but it should hopefully offer better results for those with shorter ear canals. This is just a first try based solely on measurements, as I cannot verify the result with my own ear, I need your help and feedback to maybe optimise this tuning even more by those who get the peak around 7000Hz:

I also tried creating a setting for a resonance frequency of 7500Hz, although I am not sure if many will really hear the peak that high. Please let me know if this sounds better for you:

I don't think there is need of additional tunigs for even lower resonance frequencies, like 6000Hz, because with current couplers it's very hard to measure IEMs inserted that shallow, apart from that the main peak which I hear at 6500Hz will "disappear" at frequencies lower than that, and I cannot quite estimate how much the other range will shift, thus it would need to be fine tuned by ear by those affected. It's only at frequencies higher than 6500Hz where the peak can become quite obvious, thus the additional tunigs are needed.

Please let me know your findings. I am curious to hear your opinion.

To visualise the problem of the shifting resonance frequency depending on ear-canal length or instertion depth I prepared a measurement with my current tuning at 2 different insertion depths. Green is how I perceive the sound, blue is the same tuning but inserted deeper (or simulating someone with a shorter ear canal):

In the next measurement you will see all 3 EQs optimised for the given frequency, green is the 6500Hz EQ inserted to 6500Hz, blue is the 7000Hz EQ inserted to 7000Hz, and red is the 7500Hz EQ inserted to 7500Hz. The perceived sound should be more or less the same or at least similar but without any peaks:

The graphs are just rough FFT measurements done with pink noise, as I was adjusting the EQ live while monitoring the result. You can also ignore the strange dip in the bass region which was explained to me as some Helmholtz resonance of the coupler, it shouldn't be heard in real life.

I am currently finishing the unit for the give away and will save all 3 settings into the device, so that you can immediately select your suitable tuning. 6500 will be on index 101, 700 on 102 and 7500 on 103.