A change of 3 dB is barely perceivable, and 10 dB change is twice or half as loud. A +/- 3 dB spec is best to go off of, as it is a smaller tolerance to ruler flat linear frequency response.

A speaker frequency spec of +3/-9 dB gives you an idea of the roll off at the bottom end. The lower range at -9 dB is just a little over half as loud as the rest of the upper frequencies.

Last edited by dllewel; 02/27/06 09:43 PM.
-Dave

M80s VP150 QS8s EP500s
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