@ aetosa
,so many people put the effort to help you out man,atleast share your final results and some circuit,this will help others too. cmon man sharing is caring,spread the knowledge.
Because of such non-sharing mindset,people these days don't take interest to help others :< .So much disappointing .
I just noticed that in your latest schematic the 2.2k negative feedback resistor and series 100nF capacitor to ground cause the opamp to cut all low frequencies below 727Hz.
So the output of the amplifier has no low frequencies and no high frequencies and must sound awful.