Speakers for.....every type of music?

I'm new to this site & first time poster. I am one of the guys that receives the emails every night, reads them and tries to be informed about this "hobby". A little background. I got into stereo early but never pursued it due to drumming, so I am only trying my best to keep up with you guys on this level. I have no gear like yours but keep a modest system that I have pieced together with whatever change I had. But I saw something interesting tonight on the popular discussions about a certain speaker not being a good "rock" speaker. So what do you recommend I think about when looking for speakers when I listen to everything? This is not a joke, I listen to almost every genre of music: classic, jazz, metal, thrash, world, easy listening, disco, you get the idea including vocal only. What say you fine gentlemen about my particular dilemma on your level? I am looking at used Advent & KEF speakers but will they fill my needs? I realize sound is a personal taste but in which direction might you think about?