I think "tight" is a very bad terminology.
Your sub will not sound "tight" if its not integrating with midbass properly (eg you need to level match them, but overall flat response isn't necessarily "good", ie see fletcher-munsoon curve). If your sub distorts a lot, some people find it offensive and they say its not "tight" anymore.
Some people say it sounds "tight" if there's snappy midbass, maybe midrange for some?
My "tight" might be different from your "tight".