Wayne Parham Messages: 18758 Registered: January 2001
Illuminati (33rd Degree)
PiAlign recommends 4 cubic tuned to 30Hz with a 2.25" x 4" x 3.6" long rectangular port. You can also substitute a cylindrical port, 4" diameter and 4" long with excellent results. The system -3dB point is 37Hz and -10dB at about 27Hz.