Sorry for my ignorance, but I'am shocked because of the effort to retrofit or "mimic" a beats audio!? I agree that the std setup is mediocre at best, but isn't it much more simple (and maybe as effective?) to just updrage the speakers, fit in an amplifier of 4x50Wrms@8Ohm and throw in an active subwoofer 150Wrms under the drivers' seat?
I'am not a purist, far from, but i just bought this
cupra 300 Mk4 and the disappointing std sound made me think about possible updrades already (after two weeks of ownership). The midrange is almost obsolete, but seems logic since there is no driver for it except at the bottom of the door (!?), and the bass is boomy and immediatley saturated at moderate amplitude levels already!? who has ever given a "go" for such a poor audio set-up I wonder?