My tweets must not be too loud then, cause they don't "move" any air... The sound they make is vibrations. "Moving air" has more so to do with frequency than anything else.
Loudness is measured in different forms. The loudness you refer to with your tweeters is based on intensity (w/m^2) and distance, not frequency based. Moving air as far as compression is concerned is of course the factor of the measurement of Pascals, or pressure converted directly to SPL, but dB reference is related to both intensity and pressure in all forms.
you are confusing the terms and relationship between the two.
The intensity is based on energy, so if your tweeters produce a directive high energy transfer, they will be loud to the ear based on vibrations yes. But in sub frequencies, we also have the psi relation to pressure in measurement terms. Moving air can be accomplished without an acoustical source, and it can be metered just the same output, such as blowing into a meter. But the intensity, or energy, from the sound is another form of measured "loudness" to a meter. Both are relative to their own units of measurement and both can be transformed into the form of dB logarithmic output (better for audible accuracy).
Pressure is related to a 3d field of all dimensions, where as intensity is a directive source of transfer from point a to point b. It uses all planes as pressure, but is again, measured differently.
Your reference to "loud" in the sense of a tweeter has not much to do with the dB pressure units of measurement more so it does with intensity units of measurement. Therefore, tweeters can hit say, 120dB a lot easier than one may think without moving an inch. Vibrations and fluctuations or oscillations as we call it, take the same form of transferred energy into two related fields of acoustics.
Do not confuse the two.
