ffmpeg -i in.mp3 -af anequalizer=c0 f=70 w=100 g=-24 t=0|c1 f=70 w=100 g=-24 t=0, anequalizer=c0 f=4000 w=7500 g=-24 t=0|c1 f=4000 w=7500 g=-24 t=0 astats=metadata=1:reset=48,ametadata=print:key=lavfi.astats.Overall.RMS_level:file=log.txt -f null -