 Air core or Iron core?
I'm building a three-way passive crossover and was wondering the pro's and con's of these two types of inductors. I will be using a 4mH inductor for 300W RMS on a single Kicker Comp VR 07CVR104 wired in series for an 8 ohm load. I will be using a 100uF 100V non-polarized capacitor on each of my 4 ohm Polk Audio db 690's positive leads at 100W RMS.
Does this sound like a suitable setup for this application? One of the amps in my van is tri-way capable and I am going to build a sealed enclosure to go between the front seats and take advantage of that extra untapped 300W of RMS power. | 
