Digital_Thor
Senior Member
Now... that's interesting. I use a fourth order on my 4 subs too, and seem to get pretty nice results, when merely following his advice, on having the mains with no high-pass, or at least a first order. So I have a first order on my mains at 60Hz, then a different cross-over point for each sub, but with high enough filter, for them not to be localized. Now, when I measure in the seated position, there only seem to be variance around the area where my subs cross - when I move the mic half a meter around where I usually sit.My understanding is that Earl's subs are bandpass subs, so their top end has a built-in third order lowpass function before any additional filtering.
My experience with distributed multisub systems has been that it's a good idea to aggressively roll off the top end of any subs that are positioned well away from the main speakers (like alongside or behind the listening area), so they don't betray their locations by passing audible upper bass/lower midrange energy. I use a 4th order lowpass filter, and my understanding is that that's what Earl uses as well (3rd order acoustic lowpass + 1st order electrical lowpass).
Another thing. I find it to be more balanced, with woofers that are minimum 8", when combining them with subwoofers that are 12" and 15". The overall impact and SPL seems more balanced this way. Tried with 6,5" woofers, since they only have to play down to 60Hz.... but I can't make it work like with bigger woofers.