Reprinted from Home Theater Magazine, May 2005
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Your projector may not be the only problem-plagued component in your home theater system. Subwoofers typically suffer (not in silence, unfortunately) from the interaction of sound waves being radiated by the sub itself and those reflected off of parallel walls in a room. The resulting room modes cause an uneven distribution of sound throughout the room. While you can minimize the effects in the room’s horizontal plane by shifting the subwoofer’s location, there’s still the problem of the vertical room mode. The 8-foot ceiling height of most rooms generates a room mode that sticks an acoustic dagger in the heart of most subwoofers at around 70 hertz.
SubTrap in room with subwoofer
Acoustic Sciences Corporation (ASC), a company that’s built their reputation on acoustic problem solving (you’ve probably heard of ASC’s Tube Trap), offers a sophisticated but simple-to-implement solution to the vertical-room-mode conundrum called the ASC SubTrap.
From the outside, the SubTrap looks like a black, fabric-covered box (custom colors are available) that you might mistake for a subwoofer. Place your subwoofer on top of the SubTrap, and, in many rooms, you’ll hear a more uniform bass output that’s tighter, stronger, and more defined. It’s that simple: no cords, no plugs, not even any tools other than something to help you open the shipping carton.
The SubTrap works in three ways. First, it raises the subwoofer up and out of the vertical room mode’s low-pressure zone. Second, it functions as a bass trap in the sub’s original location, dampening mode buildup. Finally, the SubTrap acts as a floating platform, mechanically preventing the subwoofer’s vibrations from transferring to the floor and the rest of the house.
For most subwoofer configurations, ASC recommends their 18- inch SubTrap, which can support up to 250 pounds. Fifteen- and 22-inch versions are also available for subwoofers with smaller or larger driver or cabinet sizes.
Copyright 2005 Home Theater Magazine