I have one pair of unused DCA 5.5 full rangers, ceramic coated aluminum wideband drivers with phase plugs.
Fs=50
Qts= .47
Vas = 11L
SPL=89db
Dia/Max=147mm
Power=50 watt
Spex good for a wide variety of alignments. Big magnets. I built BIB's for the first pair. Go to
www.audioroundtable.com for many many comments on these drivers. Read review of the Zigmahornet at 6moons. The 5.5 is a big step up from the 4.4
These drivers are now Unobtanium... $100 + shipping.