What are the specs of a full range speaker?

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.

Tvad, because the low frequencies can be felt through your body as anybody who has contact with a system playing super low frequencies will tell you. Only very few researchers believe that high frequencies are felt through the bone structure of the head. Anything that turns you on is all right as far as I'm concerned, but I still think that defining terms and agreeing on basics is too important a subject to always put forth the exceptions to any given rule or a way-out theory as being what should be given prominence in these discussions. Call me crazy!

Pbb, my speakers go down to 16hz, so I am familiar with "room shake" and feeling low frequencies in one's body. As far as HF extension, I was just posing the question without any intention of being argumentative. Since several supertweeters are marketed, and since people who buy them like their system's sound better with them than without them, it seems the buyers must sense something positive. The issue is interesting.

Have we decided on the full range frequency definition? I suppose I'd cast my vote for 30hz-20khz.

I've heard speakers that are rated at +/- whatever from 30-20K that do not *sound* full range to me. They reproduce deep bass but without the *weight* I associate with truly full-range speakers. Perhaps Room Lock and Room Shudder describe that experience of weight. Do those happen automatically if a speaker reaches down to 30Hz? My guess is room interaction is a huge factor in whether or not they do.