I just purchased (4) custom FiCarAudio 18's from Jim, aka ZORA. Thank you very much Jim, I am very excited to see how these perform in the van! So here's what's in the van:
Alpine IVA-W505 DVD player. I purchased it with the intent of running an optical out cable for audio and Ai-NET cable to touch-screen interface with the crossover, Alpine PXA-H701.
All slopes are set to 30dB/oct going against the advice of CUBDENNO, who said "keep it even at 24dB!" sorry but I just can't make myself do it!
(4) Vifa XT25TG30 1" ring radiators doing a steep 66dB/oct slope 14kHz on up (yeah, I know, but thats how it is) off a Kicker SX500.2 parallel 2ohms with its 36dB/oct slope adding in the mix. Since 14k on up is such a small weak bandwidth, I had to add a PG line driver I got from my buddy in the windy city/
(2) CSS FR125S 4.5" full range XBL^2 drivers doing 710Hz-14k off a KX650.4 bridged 8 ohms
(4) Adire Audio Extremis 6.4's off (2) KX850.4's each bridged on a pair covering 80Hz-710Hz
(4) custom Fi 18's from Jim, who gave me one hell of a deal.. great guy to work with! Covering 200Hz on down. Too high? too bad! Overlaping the Extremis? yup! When I dropped the old subs down to 80Hz, I really missed the 80Hz-200Hz content from the subs. When I brought the Extremis up to 200Hz from 80Hz, I hated it! They sound different coming from the different drivers (they being 80Hz-200Hz) and I miss them when i remove either!
Enclosure is 45 cubic feet, 20" diameter port 20" long for a 24Hz tune! Subs are HPed at 6dB/oct at 20Hz for protection.
120-150 cans of Great Stuff expanding foam..so glad I didn't do all 2x4's!
Toggle switches to disable the different bands: I can kill the tweets, 4.5's, 7"ers, and subs all separately, run any combination... just subs and tweets, just mids, whatever at the flip of a switch!
Fs = 23.7 Hz
Re = 1.8 Ohms
Qms = 7.22
Qes = 0.38
Qts = 0.35
Cms = 130.0 uM/N
Mms = 300.0 grams
Sd = 1217.0 cmsq
Vas = 279.4 liters
SPL = 92.1 dB
X-max = 40mm
Power = 1,500+ watts
The top plate is 7/8", triple magnet, 2 ohm flatwound coils, single spider (8" I think), paper/kevlar cone, santoprene surround.
The 40mm might actually be X-mech one-way. A throw of 28-30mm one-way with the coil in the gap?
I LOVED the IB3s. Weak motored subs have troubles being loaded with ports... rather than peaking at tuning, my FR responce wasn't where I wanted it. I had to PEQ heavily to bring the 20Hz-30Hz region up to fight the port. Don't get it wrong, the IB3s had enough motor to bottom out even at tuning easily, its the FR curve. So i got bigger motored subs like everyone said I should have all along to get more 20Hz-30Hz rather than peaking at 30Hz-50Hz like I was. I LOVED the IB3s and plan on keeping them in my towers!