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(Dick Pierce) wrote:

(Nousaine) wrote in message
...
(RBernst929) wrote:

Hi everyone. If i have a small, square 11'x 11' listening room am i
doomed
to
have no bass? No matter whether i add a subwoofer or two? Can i never
get
any
better bass than 50hz? -Bob Bernstein.

You'll get plenty of bass. Below the lowest axial modal frequency
(about 50 Hz in this case) you'll get a 12-dB per octave reinforce-
ment as frequency falls.)

Well, no, not exactly. The 12 dB per octave boost occurs because
you're operating the room in pressurization mode from a source
that's operating in constant accelertation mode. The former condition
can only exist of the time constant of the leaks in the room are
significantly longer than the 50 Hz cutoff and the latter exists
in loudspeakers only above fundamental resonance. Violate either
condition, and your 12 dB/octave boost is compromised.

This may be true. OTOH in a previous 2150 ft3 room (with only a 5-foot open
doorway) pressure zone reinforcement was clearly evident starting just under 30
Hz. In my Corvette I can measure over 30 dB of reinforcement at 8 Hz with
10-inch woofers in a small sealed enclosures (Fsb 50-60 Hz).