Single Supply TL072 Op Amp -- Strange biasing

[poptones]

Except I would never use a ceramic for bypassing or for anything else in an audio circuit. Use a good quality film.

If you increase the coupling capacitance you reduce the lf phase shift. Modern circuitry is so wide in  bandwidth it's easy to design for 10x the bandwidth - like -1db @ 1hz and 100khz.