"To my ears, the Hsu ULS-15 MKII is just about everything you could want in a subwoofer. Its sealed design is amazingly accurate and delivers clean tight bass that suits music particularly well but is just as beneficial for movie soundtracks. The Hsu is also relatively compact and blends into a room far better than much of its competition. The only trade-offs to the sealed-box approach are a decrease in sub-20Hz bass reproduction and a few dB less of overall output (which is still pretty prodigious) compared to similar 15-inch ported designs. However the increased musical accuracy and superior speaker integration offered by a great sealed sub like the ULS-15 MKII outweighs the loss of that little bit of volume and depth, at least in my book. If you have a particularly large room (over 4000 cubic feet or so – like me) and need (or want) more bass output, just install two of these sleek little monsters. Hsu will even cut you a better deal on a ULS-15 MKII DualDrive package – currently just $1499 plus $138 shipping. Not only will you get up to 6dB of additional output, but you could then place the two subs in different locations, which will typically provide smoother overall bass response in most rooms. For anyone who cares equally about music and movie performance, the ULS-15 MKII is an excellent choice. So much so that I purchased my review sample."
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