This calculator can solve for one piston excursion parameter while changing the
other variables. For example: tell the calculator the number of drivers,
cone diameter, desired volume level, a frequency and it will calculate how much
driver excursion (Xmax) is required to achieve this assuming a sealed box or
infinite baffle alignment.
This calculator is only valid for sealed box or infinite baffle alignments.
Xmax excursion is center to peak ("one-way") which is usually half of
the peak to peak value.
These are excursion limited numbers. It is assumed that
amplification and driver power handling are not a factor.
Vented alignments will typically have double the driver's Xmax values at
F3, this shows the efficiency inherent in the vented alignment.
Isobariks should be calculated with half the number of drivers, since
all we are interested in is how large the radiating surface is and how much air
it can move. Isobariks change effective box volume and that is not what
is of interest here.
These equations don't follow the max 194dB limit in 1 atm. They
track nicely until you get to the extremes (example: 10000 drivers or an Xmax
of 300 feet or a driver with a diameter of a quarter mile). As things
get huge the point source model falls apart.