iPhone high-pass filter and tuning curve information for my Ph.D.
I'm working on my Ph.D. studying the bioacoustics of cicada. The recordings I've obtained have been taken from a wide variety of equipment, both professional grade to smartphones. The smartphones are proving to be a bit of an issue though in understanding their capabilities to get a flat frequency response from the microphone.
The main models are iPhones 5 and 6, though 8 and 12s have also been used. The only real information on frequency response I have been able to find was from a study done by Faber on early models.
The cicadas I work with generally call from 3000-14000Hz, with the average being around 8000-11000Hz. I am trying to find whether or not there is current information regarding the later models: 5, 6, etc.
More troubling is the rumor I've heard that iPhones use an internal high-pass filter to pre-process recordings when they are made. I need to know if this is true and if possible what the filter is set at.
Thank you very much,
You can contact me directly too at firstname.lastname@example.org