I use an HGS-15 with a SMS-1 that I think was Velodyne's approach to room correction before the DD series. Believe me, the HGS-15/SMS-1 pair can deliver that more felt than heard experience when a low organ pedal note is invoked and pressurize your chest when an explosion occurs in a film. Our media room is 19 X 14 X 8. The sub integrates seamlessly, and you are only aware of its contribution when it does something you know the mains can't possibly be doing, like a subtle vibration or shaking the room. The introduction of the organ in a good recording of Saint Saen's 3rd symphony is a thrill. I use an 80 Hz crossover.
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