There is one major flaw in the presented approach. The base of any hearing aid is frequency compression (in each frequency band), as the hearing impairment induce, that a patient loss the ability to hear the soft sounds, but the loud sound cannot be amplified, as the threshold of pain remains the same. Usually, the gain curve resembles two linear lines. Feel free to reach out [redacted] if you wanna discuss the topic in more depth (i designed some algorithms for hearing aids)