Labs Video: Sealed vs. ported sub box listening test
The kind of enclosure you choose for your sub will have a big impact on the way your bass sounds. In general, sealed boxes will give you bass that's nice and tight, while ported boxes will deliver bass with plenty of resonance. One isn't necessarily better than the other; which you prefer will depend on your taste in music.
To help you get a sense of the differences, a group of our advisors hit the Crutchfield Labs to do some critical listening, then discuss which types of enclosures worked best with particular types of music.