Hey there. I'm looking around for a subwoofer cabinet that can handle a suboctave E (20.6hz). The closest thing I've seen is the Accugroove El Whappo Grande - which apparently goes down to 22hz. I'm just dicking around hypothetically - though I'd like some serious answers. It would be a part of a GK1001 and GK 4x10 rig. Thanks in advance.