Just put in door pods in my old '94 Mazda Protege... 8" Genesis Physics woofer (from a Genesis home speaker from 1979, believe it or not). I expected it to do DECENTLY well... but after measuring it on LMS (Loudspeaker Measurement System)...
HOLY COW... literally, it's LOUDER at 15 Hz than it is at 100 Hz! And this is with NO EQ or crossover... just the 8" woofer, hooked directly to the output of a power amp, from the measurement computer (which generates its own test signal)!
Check this plot out! I know that just a pair of 8" isn't going to break in SPL records (but good grief... just running off the 16w/ch Alpine HEAD UNIT, it'll ALREADY make the mirrors shake!), but for me, it'll probably be all the bass I need!
BTW: These plots are of one woofer, measured from each of the two seat positions (headrests). They're meausred in very high (1/20th octave!) resolution... that's why there so many irregularities. If it was "smoothed" to 1/3 or 1/6 octave (as is the norm, for MOST published speaker measurements), it'd be much smoother-looking. Other than the peak at around 700-1400 Hz (which won't be a factor, they're gonna be crossed over at somewhere in the ballpark of 350 to 650 Hz, to a dash-mounted mid-tweet pod), it's pretty remarkably smooth for a raw plot!
