Bass, Frequency response, Etc...Noob Question


Sorry if this has been covered before, but I looked through a bunch of pages and didn't really find exactly what I'm looking for. I'm confused by many of the spec numbers provided by manufacturers with regard to bass and frequency response and how these numbers relate to real world listening. I'm mainly talking about the bass end of the spectrum here...For example, a speaker manufacturer lists a frequency response of their speaker to be 35Hz-20kHz +/-3db, which while, not quite full range, appears to provide a nice amount of bass (I know there's a LOT more to this such as room size, placement, etc, just bear with me). My confusion comes in when writers or reviewers state that a speaker with the above specs to be better suited for vocals or jazz, and not meant to "rock", while a speaker with similar specs (sometimes even not as low on the bass freq) might be recommended for rock. What makes one speaker more suited for a specific type of music than another? Is it the "oomph" and controlled power of the bass frequencies? I'm just curious as I've seen speakers that I'd consider checking out, only to read or hear that they are not suited to "rock" music (my primary listening). I know this is very vague, and I'm unable to properly articulate what I'm trying to get at (sorry it's late). I guess a quick example would be why a speaker like the Reference 3a De Capo is not as suited to rock music as say a Klipsch Heresy might be...Any help would be appreciated!
mbleming

Och!!!

I used to be a dealer for Reference 3A and used the mm de capos to party with. Great rock speaker. Keep in mind that you are after a speaker that can handle a lot of power without scorching itself. Also to much bass is much worse than not quite enough because it often gets your room resonating, just like a car subwoofer gets the whole car bouncing. What you don't want are big 10" or 12" woofers which by their nature can not move as quickly as your smaller midrange driver and tend to sound sluggish.
This thread has got me thinking. I recently replaced my Kef Reference 3s (40Hz on the low end) with von Schweikert vr4 iii hse (20Hz on the low end). I listen to a fair amount of jazz, and the lowest note on an acoustic double bass is 41HZ or thereabouts, but the VRs, w/o sounding at all boomy, seem to get WAY down, even on instruments that don't get below 40Hz. Am I hearing harmonics "below" 40HZ, or it just the greater volume of air that the VRs push at 40 Hz?
I'm not looking for over-exaggerated, overblown bass, but I just want the speaker to reproduce (with some degree of accuracy and authority) what is on the record. I have to admit, choosing speakers is confusing! Especially when you can't audition them easily!