6.5" MIDS WITH TWEETERS "CRYSTAL"

OK, I HAVE 4-CRYSTAL 6.5" SPEAKERS THAT I WILL BE MOUNTING, DOES EACH ONE REQUIRE THAT I MAKE A LITTLE ENCLOSURE LIKE I WOULD WITH A SUB BOX OR SHOULD I NOT WORRY ABOUT AIR SPACE AND JUST MAKE A SPACE BIG ENOUGH FOR THE SPEAKER AND CALL IT GOOD?

SORRY BOUT THE CAPS.