Thanks Mark.Not sure I fully understand.1. The mems mic has pdm output, from 4th order sigma Delta. Is all the filtering you've quoted in addition to that ?
2.why will phone reject 20+kHz ?
Eg the fft spectrum analyser app spectroid gives an option to.sample at 96kHz......
3 what platform would you recommend for such a project with say 30kHz limit ?
Many. thanks.PS in OP I said read from the audio channel, I meant read from the mic channel obviously.