If you have too much bass, why not tune it down for lower output.

I use 2 15" subs in a SQ vehicle b/c physics says it can produce low frequenies easier.

For an SQ vehicle 1 10" would do for loudness in 35 Hz to 110 Hz range. But to produce 40 to 18 Hz with low gains use 15" 's.

There is only one 12" I know for producing low sub frequencies, IDQ v2 by Image Dynamics.