After feedback from customers who wanted a subwoofer that was friendlier to living room decor than the behemoth ported boxes and tall cylinder subs Hsu had been producing, Hsu Research released their first sealed subwoofer in 2008- The ULS-15. Hsu had already built a solid reputation for deep-digging, accurate, and affordable subwoofers. The caveat had always been size per Hoffman’s Iron Law which states that you can have two of the following, but never all three: sensitivity, small enclosure size, and deep bass. Low sensitivity necessitates a powerful amp and heavy-duty driver, which raises costs considerably. So, in an effort to make their subwoofers affordable, Hsu had traditionally decided to compromise on size instead. However, a strong demand for subwoofers with a more attractive size and shape prompted Hsu to break with their tradition in the ULS-15. While the ULS-15 went on to successfully fill its niche in the Hsu line-up, the years went by and new technologies made a compelling case for an overhaul, which brings us to the ULS-15 mk2.

The ULS-15 mk2 shares some of the same design features of the mk1, but also some important differences. However, before we get into design discussion, let’s begin where most users would with the ULS-15 mk2: unpacking.

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