The Air Compliance for a Subwoofer calculator computes the Air Compliance volume for a subwoofer speaker based on the Box Enclosure Frequency, Speaker Resonance Frequency and the Enclosure Volume.
INSTRUCTIONS: Choose units and enter the following:
Air Compliance (AC): The calculator returns the air compliance in cubic inches. However, this can be automatically converted to compatible units via the pull-down menu.
Air Compliance or equivalent air compliance is a relative measure of the volume of air that has the same compliance ("springiness") as the sub-woofer's driver suspension. The Air compliance is proportional to the Volume, so generally less air volume has a lower air compliance factor corresponding to being more "springy", while more air, a larger Air Compliance represents a "looser" suspension.
The formula for Air Compliance of a subwoofer is:
AC = `(F_b/F_s)^(1/0.31) * V`
where: