I'd recommend researching the right amp first. Like a speaker, an amp does not necessarily have the same sonic strengths across the frequency spectrum.
Once you've settled on an amp, it then becomes easier to find the right speakers to match your amp.
If you are bent on spending $10k on a used pair of quality-oriented speakers, then it should matter very little what type of music you enjoy, or even what size room you have, unless of course the room is abnormally small or large.
Speakers in this price range and up should excel with most any type of music.
-IMO
Once you've settled on an amp, it then becomes easier to find the right speakers to match your amp.
If you are bent on spending $10k on a used pair of quality-oriented speakers, then it should matter very little what type of music you enjoy, or even what size room you have, unless of course the room is abnormally small or large.
Speakers in this price range and up should excel with most any type of music.
-IMO