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You should set it to 1/2 an octave below tuning (which is conversative itself, especially w/ today's high-Xmax subs), which is 0.75*TUNING and, in this case, is 26 Hz ...
Setting the SSF @ 32 Hz means you're already -3 dB @ 32 Hz, which means you're taking a huge portion of output away @ tuning, which is highly unnecessary considering that's where you have the least movement ...
Damn n00b '06ers ...