Normal
Re: 12" driverThe pressure pot gain of the few cars I've stuck a measurement mic in starts between 60Hz and 80Hz, and tracks pretty closely the 12dB/octave theoretical output increase you would expect, so if you are trying to keep the response pretty flat, 60Hz is a reasonable F3 target for whatever sealed box you might choose to design.That said, what many humans associate as "flat" in a typically home living room usually has a slight upward tilt in the low end, due to the pressure pot gain of the small listening room. When I do system tuning "flat" in larger rooms, where the pressure pot gain starts occurring below the frequencies reproduced by the PA, I sometimes add slight upward tilt in the low frequencies to make the system response more closely mirror that of listening in a small room.
Re: 12" driver
The pressure pot gain of the few cars I've stuck a measurement mic in starts between 60Hz and 80Hz, and tracks pretty closely the 12dB/octave theoretical output increase you would expect, so if you are trying to keep the response pretty flat, 60Hz is a reasonable F3 target for whatever sealed box you might choose to design.
That said, what many humans associate as "flat" in a typically home living room usually has a slight upward tilt in the low end, due to the pressure pot gain of the small listening room. When I do system tuning "flat" in larger rooms, where the pressure pot gain starts occurring below the frequencies reproduced by the PA, I sometimes add slight upward tilt in the low frequencies to make the system response more closely mirror that of listening in a small room.
