On December 18, 2017 at 09:31, FP Crazy said...
I always assumed that the woofer drivers in standard ceiling speakers are "infinite baffle" Q specification? Meaning they typically sound better in a large enclosure (like an attic). Not spec'd for some small sealed enclosure?
Many speakers are considered working in infinite baffle (free air) when the enclosure space is at least 2x-4x (can't remember which) more than the Vas parameter (Compliance equivalent volume). Whether that be an entire attic, truck of a car, or a box built larger than that.
Generally speakers made for infinite baffle use, will also have a low Cms parameter (stiff suspension).
Most in-wall / in-ceiling speakers are going to fall in-between 1-2 cubic foot to be IB. But you only need that much space if you want to play to the lowest frequency with no changing of the sound. Many times using an enclosure 1/2 that size will be fine with little change to the 'usable' low frequency.
With a subwoofer in use and a high-pass xover on the built-ins, you would only need 1/4 of that space or less.
