Any speaker can play R&R, blues, grundge, hiphop, reggie@mozartfan Any speaker can play classical too. The more finesse the speaker has, the better it plays all genres. Seriously- if you could find a way to make a speaker genre specific you'd be a millionaire overnight. The reason it can't be done is musicians all use the same set of frequencies and all humans have the same set of hearing perceptual rules.
Jazz requires a bit more finesse.
CM (at least full blown symphony orchestra) requires even more finesse/nuances/fidelity vs all other musical genres.
Full symphony orchestra requires a ~~special speaker~~Midrange demanding.
Its simply a mistake to lump all 'R&R, blues, grundge, hiphop, reggie' into the same spot when there is so much variety and nuance in modern music- and so much variance in recording quality, just as we've seen in classical music since the dawn of hifi. You want a nice rock recording- side one of King Crimson's Islands- you'll hear nuance, detail (if you have a good pressing) - it sounds like they are in the room. Or try a Pink Island edition of ELP's first album... Keith Emerson BTW was a master at the keyboard and integrated a variety of classical pieces into his compositions. And not surprisingly, if you want to hear these recordings at their best a speaker that does classical very well is going to do it, simply because the speaker does not care what music you play- and neither do the amps or preamps!