Cardioid Sub Woofer Arrays

Directional subwoofer arrays are becoming common on tours and in higher end installations and increasingly speaker manufactures are bringing products out that provide directional or cardioid subwoofers from out of the box products. Here are some good reference material for techniques and products including background info, creating and using directional subwoofer arrays.

Products

Meyer Sound Products

PSW-6 : High-Power Cardioid Subwoofer (one of the first off the shelf product directional subwoofer I became aware of) it has two 18 inch and four 15 inch woofers – two of the 15 inch woofers face the back:

M3D-Sub : Directional Subwoofer – Meyer’s dual 18 inch front facing and dual 15 inch rear facing touring subwoofer:

General Articles

http://www.doctorproaudio.com/doctor/cajondesastre/pdfs/Downloaded_from_Doctor_ProAudio_com-SettingUp_cardioid-Joan_La_Roda-DAS_Audio.pdf

Seems like all the rage but not everyone thinks so:

Check out this discussion: (http://forum.speakerplans.com/how-tocardioid-sub-arrays_topic26007.html)

“For sub-bass control I’m not convinced there is any advantage over just pointing all the subs forward & forming a wide horizontal array, in most circumstances. I try to induce as much diffraction directivity as possible & then the radiation pattern tends to be cardioid shaped anyway.”

“I do have and use Q-Subs and S2 cabs. The CSA method does work to some extend, but you need more gear ( cabs and amps ) to end up with less SPL than straightforward non-CSA. I tried it several times in various venues from very small to rather big and from my experience it’s a small benefit at best at the cost of more gear. The feeling creeps on me that it’s a marketting ploy to sell more gear because they ( not only D&B ) convinced you bass splill at the rear is THE BIG problem. But is rear spill really that big a problem ? I admid it can be in some cases, but an environmental problem primarly in open air gigs. Every time I used it, musicians start complaining”

The best I have seen on this topic is:
Phase Wavelengths: The End Fire Cardioid Array made visible

http://bobmccarthy.wordpress.com/2010/01/27/cardioid-subwoofers/

http://svconline.com/mag/avinstall_bass_not/