You are absolutely right about what you say. Efficiency has no effect on the frequency balance of a speaker. Straight line in, straight line out. BUT the signal (noise) 'in' in this instance is tilted toward the high end of the spectrum, and the speaker is just passing along what it is getting; noise that is accentuated in the high end. Horn or not, you'll hear more energy from the tweeter than the woofer with this type of noise.

If you've used a spectrum analyzer to check the frequency response of a speaker, you've undoutedly used 'pink noise' as the signal source. This type of noise should display a flat line across the frequency spectrum on the analyzer. It sounds just like it looks, equal across the band. "White noise" is never used as a signal source, and if you looked at it on a spectrum analyzer, it would be a rising line from low to high frequencies. It sounds just like it looks. White noise is the type of noise that is generated in electronic equipment. Pink noise is artificially produced by imposing a 3db per octave filter on a white noise source.

[This message has been edited by soundhound (edited November 25, 2002).]