4 H 52 06 16 SD is an underhung magnet-system Flexunits, that works well as a fast, dry-sounding midrange but also in a relatively small 2-way system. Works well in 10-15-liter ported or sealed box between 5 and 12 liter depending on desired Qtc. Can be built with J- or I-magnets to adjust sensitivity according to the Flexunits idea.
Flexunits
4 H 52 06 13 SD Midwoofer
Specification
FS:48 Hz
VAS:16 ltr.
QMS:1,75
QES:0,41
QTS:0,33
Efficiency:88 dB