I use a SubDude under my Velodyne HGS-15 to good effect. It tamed any tendancy to boominess, and audiophiles who have listened say they are not aware of the sub, because it integrates well with the KEF 104/2s. The sub is placed behind one of the KEFs, about a foot away from the corner and close to the rear wall. You would not point to the sub as a source of sound, but you would have before the SubDude.
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