Wayne Parham Messages: 18787 Registered: January 2001
Illuminati (33rd Degree)
VTC is the volume of the front chamber and ATC is the average cross-section of the front chamber. Set VTC to the volume of the cone and ATC can be probably a little less than SD. The shape of the front chamber is a cone, so cross-section area is tapered. You can vary these parameters a little bit and they don't do much to response. For example, the additional volume made when the driver is offset from the baffle with a gasket or thin spacer won't make a measureable different. But if you double the front chamber volume, that will.