Size of the enclosure matters, too.

Look, there is A LOT of science in loudspeaker design, and you can't just reduce it to one factor (cabinet design) and generalize to "all".

Not ALL ported designs have greater bass extension than similarly sized sealed enclosures. There are dozens of other factors at play.

In addition to the excellent points made by Jay, Steve and Adrian, you also have to consider potential tradeoffs relative to SPL v. extension.

If loudspeaker design was "easy", people wouldn't get paid to do it or write books about it, or surf the internet all day.

bibere usque ad hilaritatem