GMK’s Subwoofer Cone Area Calculator (Sd)
Quickly compare setups by cone area (Sd). Enter size + quantity to see total area and equivalency.
Estimates cone area (Sd-ish) from nominal diameter.
For exact Sd, check the manufacturer spec sheet.
Notes: This uses circle area (πr²) with the nominal diameter. Real Sd is usually smaller due to surround + cone geometry.

