Louder music sounds better if you have shitty speakers. When I bought my set of studio monitors, I realized that I (unconsciously) listened at a much lower volume, simply because the clarity was already close to perfect at that volume.
After he and the sound system moved in, I listen to music (of all kinds) quite a bit louder in our living room: My earlier crappy sound system just didn't sound good at high volumes while this system sounds beautiful as high as we care to crank it before we decide that we're being too unreasonably inconsiderate to our neighbors.