Subwoofer Reviews

VTF-15H MK2
Performance
Features
Build Quality
Value

VTF-3 MK5 HP
Performance
Features
Build Quality
Value

AT A GLANCE
Plus
Tremendous bass output
Excellent value proposition
Highly flexible setup controls
Minus
Won’t win any beauty contests
Heavy!

THE VERDICT
Both subs have plenty of bass per dollar and offer lots of adjustments to fine-tune the performance to fit your room.

Robert Southey was an English poet and author whose version of the fabulous children’s story “Goldilocks and the Three Bears” was the first one published, in 1837. While the tale has entertained kids for 177 years, little did Southey realize that his story is a fitting metaphor for modern subwoofers. Like the three bears’ porridge, chairs, and beds, subwoofers come in all shapes and sizes, and finding the one that’s “just right” for your particular room can sometimes require sampling different subs and room positions in order to get the best bass response.

Poh Ser Hsu immigrated to the United States from Singapore to get his graduate degree in civil engineering in the early 1980s and began making subwoofers soon after. Like many American success stories, Dr. Hsu turned his hobby into a new career in 1991 when he started selling his cylindrical subwoofers via mail order. And when use of the Internet exploded later in the decade, he was in the right place at the right time to sell his goods to a much wider audience, as the home theater boom was just beginning with the launch of DVD. He eventually moved away from tubular designs and into more conventional boxes, but his goal of reproducing deep and accurate bass response has never wavered.

Hsu Research offers nine subwoofers via their Website. The two newest models, the flagship VTF-15H MK2 and the step-down VTF-3 MK5 HP, up the ante from their previous offerings with a beefier 15-inch woofer—almost 7 pounds heavier than the woofer in the original VTF-15H that was well reviewed by S&V’s predecessor Home Theater in 2011—and a 250-watt jump (600 watts rated) in amplifier power.

Pricing on the two subs definitely falls into the high-value range of high-performance subwoofers (though you’ll cross the $1,000 threshold when you factor in shipping, at about $1 per pound, for the VTF-15H MK2). What’s more, Dr. Hsu’s subwoofers are a tinkering audiophile’s dream, due to a plethora of setup options that allow you to customize the settings to your particular room, in order to get the most boom for your buck.

Fraternal Twins
Differences are few between the two subs. In fact, they share the same woofer and BASH amplifier. The VTF-15H MK2 includes balanced inputs (absent from the VTF-3 MK5 HP), and the cabinet size is 4.5 inches deeper and 0.75 inch wider. Theoretically, this means it should have slightly deeper bass extension, play a little louder, and (due to its larger ports) have less deep-bass compression and port noise. Both subs come in one color and finish—black satin—and neither would fall into the dainty category, with the larger sub weighing in at 110 pounds and its smaller sibling at 85. Needless to say, you’ll be pushing these babies around the room in lieu of lifting them—and you’ll probably want a friend there to help you.

The custom-built BASH amplifier is rated at 600 watts, with a claimed peak output of 2,000 watts. The VTF-15H MK2 has two matching triangular ports. You can leave both open, close one, or block both with the supplied foam inserts to make the sub a sealed enclosure. To optimize the sub, there’s a two-position EQ switch on the back panel offering five different modes of operation for maximum headroom or maximum extension, depending on how you set the EQ switch and utilize the foam plugs. The only warning in the manual is to not operate the sub with two ports open and set to EQ1, as this can damage the driver and void the warranty.

The VTF-3 MK5 HP offers dual ports as well—one 3 inches in diameter and the other 4. If you’re going to run the sub with only one port open, you’ll want to seal the 3-inch port and use an EQ1 setting for max extension or EQ2 for max headroom.

Both subs offer an adjustable Q control on the amplifier to manipulate headroom, response, and better leverage room gain (continuously adjustable from 0.3 to 0.7.) The rule of thumb when dialing in the Q control is that the lower the Q, the tighter the bass. (Secondarily, says Dr. Hsu, the higher the Q, the less deep-bass headroom you’ll get.) Additionally, both subs offer similar back panels that include speaker- and line-level inputs (plus the aforementioned balanced inputs on the VTF-15H MK2), an on/auto/off power switch, a phase adjustment, and a volume control.

Setting Up Is Hard to Do
I’ve had many subwoofers in my room throughout the years, and my go-to spot is the front left corner. However, neither of the Hsu subs would fit there, so I needed to find a new location. Fortunately, Dr. Hsu personally delivered the subs to my house and was kind enough to help me unpack the VTF-15H MK2 and customize it to my room.

Unfortunately, my preferred listening spot is located in a bass null, which can cause setup issues with subs—one of the reasons why I employ Audyssey correction in my pre/pro. But when reviewing speakers, I try to find the best position for them and don’t employ equalization until the very end of the evaluation period, so that I don’t colorize the testing. That said, Dr. Hsu and I had a heck of a time finding the right placement for the sub.