High End jargon; your take

Tight= Tight bass is bass that you actually hear as well as feel. Bass that is tight is controlled and focused. With tight bass the bass is not just an indistinct rumble. You can actually hear the attack on the bass strings and the detail in the strings. It is not easy to describe. The attack on the strings and the resulting low frequencies maintain a certain coherence. In a series of rapid notes on an electric bass for example, tighter bass means you hear and feel each attack and note distinctly whereas if the bass was not as tight you might not be able to make out the line as clearly and the line would be more of a rumbly blur.

Warm= This means different things depending on the context. Warm can be the opposite of "cold and analytical." This usually means less detail, less neutrality, or less instrument separation but a more pleasing presentation.

Warm also can mean pleasing in the higher frequencies--easy to listen to and not harsh or bright sounding, bright meaning too much treble or shrill sounding. The opposite of warm in this context is not "cold" but rather "fatiguing" or "bright".

hifi - totally nondescriptive although I can see how it might be used to try of explain a sense of higher resolution

Blackstonejd- In other words: Pitch resolution and speed= "tight" Anyone that has been standing(or sitting) near a well played drum set will know what "tight bass" sounds and feels like. Without it there is no sensation of the tautly stretched drum heads, stuck by wooden sticks, their resonances and decay. Likewise: The plucked strings of a double bass, and the resonance of it's body are lost without a system that's capable of "tight bass". I call that "rumbly blur" of an underdamped bottom, "one note bass", because it renders everything in the lower frequencies the same. ie: No distinction between the kickdrum and bass(guitar or upright) when playing the same line. Of course: If you never experience the sounds live, or are seated in the back row/against the wall/in the corner(cheapest seats), where everything is mud anyway: You don't know what "tight bass" is, and can't relate. BTW: My son is a drummer, and one of my best references when tweaking the bass of my system.

Rodman,

You're right regarding drums and bass!

BTW: I think the ultimate test material for bass "tightness" is Bela Fleck and the Flecktone's UFO Tofu album. Flight of the Cosmic Hippo isn't bad either. ;)

I third Rodman's comments - spot on - exactly right - that is just how it all sounds! Well said! Although a high Q system (underdamped) can sound pleasant (with plenty of bass for a small WAF friendly design) it will not convey the lower octaves clearly so that you can feel the "texture" of bass sounds. There is actually a stunning amount of information in the bass - every individual track should actually sound dramatically different in the bass just as every midrange and treble usually does.