What are the specs of a full range speaker?

Pbb has a good point, what is the most reasonable range, which he says is 30hz through say 16Khz. Hoover joins in with agreement and is hapy to see someone actually post this. My speakers go to 40hz and so far have been satisfactory enough. IOW when I play the New Orleans Jazz complitaion and another compliation Blues cd, both very high quality sound recoding, the bbass fills the room. Thats at between 1/4, 1/3 volume on my 40 watt tube amp. But considering I mostly listen to classical, i'm now ready to get at those fq's from the bass, cellos, tubas, timpini's, the 30hz-40hz. IOW I want a new experience from my classical with that added bass. Now the 20-30hz's I'll be missing. But as Pbb mentions just how important are these super low fq's, how much will they be missed? How often in classical are these fq's there? In solo piano there's not much below 40 I'm sure. Yes the piano can go as low as 20, but how often do composers work in that low fq in piano scores and even in orchestral. Rarely.
And the upper range, who knows from human hearing when a tweet rolls off at 20hz, and other tweets at 22Khz? I'd guess on the jazz and blues cds there is more going on in the 20Khz+ range than in my classical. But those tweets that go up to 22Khz+, are they delivering quality superhighs, 22K-25Khz? Are are the highs sort of "fake" sounding, tinsel-y/ metalic, IOW fatigueing? That is do tweets that go as high as 25hz+, is that upper range for real? Also is they are designed to go too high, then how well do they meet the mids of the lower drivers? Which is why my seas' tweet does not sparkle, but instead has a bigger bottom end and meets the midwoofer with seamless resolution. I do not lmsii the 22hz+ that the Seas seem to not deliver on.
So I'd say full range is 30hz - 18Khz as Pbb mentioned.
I'll read the other posts here. Some great comments are being made and we are carrying audio one step further to a PROPER understanding. For too long audio knowledge has been in the dark ages, and audio labs have taken full advantage of our ignorance and pushing its bull on us.

Muralman:"all I know is most systems are truly deficient in the 20-20Khz range(meaning problems in qulility of reproduction of the original source)..I don't knwo why anyone would want to perfect what they can't hear, before they (first) get right, what hz's they can actaully hear". Agree, before we run after the 20hz-30hz/20K hz-25Khz, first how does the speaker reproduce the 40-18K hz?
For me its more important taht a speaker offer a seamless image in the meeting of the bass/mids/highs,, that it is to get at the 20-30 and 20Khz+ range. Actually 30hz is my bottom range I'm interested in. I alreday have a speaker in mind that fits the characteristics I'm looking for.

Goroi- I was referring to speaker systems of any kind, not just single driver systems.

Sogood51- I like your "room lock" and "room shudder" concepts.

Newbee-The passage says "reaches down into the 30s WITH SOME WEIGHT". Is that meaningless? The meaning was clear to me but maybe it didn't translate well.

Pbb- Thanks for taking this where I had hoped it might go. What use is the inaudible? I personally feel that the whole absolute sound model steers us away from a relaxed and pleasant music listening experience and causes us to grip our chairs and squeeze the last note out of our equipment.
Why are so many of us so obsessive?

Inaudible content on the low end can be detected by the body because it shakes the floor, ceiling, walls, etc.
How would we detect inaudible high frequency content?

For me above 15.5 Khz I hear nada....so I would agree that linearity in higher frequency response in a system is not very important to me at least above this level.

I respect that some can hear up to 20 KHz and when I was younger I could hear somewhat higher than my limited upper range today... so it is relevant.

Above 20 Khz, however, I have a hard time accepting there is any need for a system to reproduce these...maybe my dog appreciates it.

Low frequencies seem audible somewhere between 15 and 25 Hz to me...not that I don't hear something lower but that I suspect the sub excites vibrations in the walls which may be principally what I am hearing or feeling (some of these excited vibrations undoubtedly include higher harmonics and rattling which are clearly audible and are really added "distortion" but they make for convincing effects in movies). I have not found that higher frequencies (above my hearing ramge) are capable of inducing lower frequency audible harmonics in the room...the sound or test tone just disappears for me.

IMHO, due to the range of my hearing and for the added distortions that ultra LF excites, extended low frequency response is more important than extended high frequency response.