i discovered my paranoia about not being able to hear 15Khz sine waves was because the M50s aren't flat enough and have a big recession in the 13k+ range
i wonder if the VMP cork mat was warped because of the cork or because VMP were just awful at shipping (i do like my acrylic platter though and its resonance might be why i prefer vinyl)
note i legit love my turntable and cartridge... i feel dumb for questioning greener grass.. the only real upgrade it seems i'll need is a new stylus in a year or so