please forgive me if this is a stupid question. i've been dabbing into home audio occasionally for the past 5 years and the more i learn, the more questions i have.

how come a lot of speakers have more than one of the same speakers types? i see a lot of axiom speakers have 2 mid ranges and 1 tweeter. i see some of the center channel speakers have 3 mid ranges and 2 tweeters. wouldnt this sound just as good with 1 of each? my mediocre yamahas even each have 2 mid ranges, 1 tweeter. my old sony home theater only had a single mid range per channel no tweeter. i know sony and yamaha speakers are far inferior to axiom and bose(although bose imo is way overpriced). i do see though on some axiom surround speakers that they face the tweeters in opposing directions which i can see makes sense because i assume that way you have a wider area for sound. but what about the others like the center where they face the same direction?

so does having multiple of the same speaker on the same channel really improve sound? im sure they've done testing and it is better or they wouldnt have done it but what is the reasoning behind it?