The low, low lowdown on the Hsu Research VTF-3 MK4 subwoofer

Hsu Research VTF-3 MK4 subwoofer

(Credit: Hsu)

Just as with speakers, size matters with subwoofers. Pint-size subs can make bass, and the best mini subs can deliver fairly deep bass, but the volume capability, bass quality, and definition of baby subs can never match what you can get out of something like the $449 Hsu Research VTF-1 MK2 sub I reviewed on this blog last year. That bruiser measures 18x14x17 inches, and has a down-firing 10-inch woofer and a 200-watt amplifier. It's the best under-$500 home theater and music sub I've heard, but I was curious about Hsu's $699 VTF-3 MK4 monster, to see what it felt like. Felt is the best way to describe the difference in sound quality, as it's a much more visceral experience.
This 74-pound brute is bigger, at 22.25x17.75x25.75 inches, and features a 12-inch woofer and a 350-watt power amp. The cabinet feels extra-solid. My review sample was finished in satin black, but VTF-3 MK4s are also available in real Rosenut veneer for $799.
Room size should play a major role in determining the optimum subwoofer size, but how loud you like things is also a factor. That's why Hsu makes 10 different models; the company can help you pick the right one for your needs. A big sub like the VTF-3 MK4 will be overkill for small, under-500-square-foot rooms, but if you're lucky enough to have a big listening room, splurging on a big sub makes sense.
Just like the VTF-1 MK2, the VTF-3 MK4 can be fine-tuned to deliver the type of bass you want. It has two large bass ports on its right side panel that when you unbox the sub are sealed tight with large rubber plugs. By leaving the plugs in or out and adjusting the VTF-3 MK4's "EQ" and "Q" controls, you can get rich, very full bass; or lean, highly defined bass; or anything in between. I prefer cleanly defined bass, because with music I want to hear the pitch of the bass note rather than just a bloated bass sound. Point is, you can dial in exactly the type of bass you want.

The Hsu VTF-3 MK4's rear panel hosts more fine-tuning controls than most subs have.

(Credit: Hsu)

I played the VTF-3 MK4 first with my KEF LS50 bookshelf speakers and easily achieved a smooth blend. I was never aware the bass was coming from the sub; it seemed to come from the speakers. The speakers sounded like big towers, but since I wasn't using an AV receiver with bass management the LS50s' ultimate volume capabilities were limited. If you like to play loud and have small speakers, use an AV receiver to reduce the bass demands on the speakers. The receiver's bass management will redirect bass to the subwoofer, lightening the load for the speakers. I didn't feel a need to push my small speakers superloud, so I didn't use a receiver. My old NAD 3020 stereo integrated amplifier worked quite well with the LS50s and the VTF-3 MK4.

I next demoed the sub with a couple of tower speakers, the Tekton Enzo and Zu Omen DW (review in the works), and the VTF-3 MK4 added more than just bass to their sound. The speakers sounded bigger, and sound stage depth improved to a significant degree. I know that might not make sense -- why would adding more low-end improve stereo imaging? But it absolutely does.
I had the VTF-3 MK4 's crossover for these stereo tests set very low, 40Hz, and the VTF-3 MK4's volume level was low enough to not thicken or muddy the towers' bass one bit. In fact, most of the time I was barely aware the VTF-3 MK4 was doing anything, until I turned it off. The towers then sounded a lot smaller and rather thin. To put it another way, pairing a great sub with a set of towers improves the speakers' overall sound, so they sound like much more expensive speakers. I've never heard an under-$10,000 tower speaker that can touch the $2,699 Enzo-VTF-3 MK4 combination's bass power and definition. Adding a smaller, but still incredibly potent Hsu sub, like the VTF-1 MK2 with the Omen DW, would make for a killer $1,449 pairing.
Very few tower speakers really deliver the deepest bass frequencies, even when their specifications claim impressive low-frequency numbers. They're nice in theory, but the problem is that for the speakers to deliver the deepest bass, they would need to be placed close to walls and corners, and that inevitably compromises the speakers' stereo imaging and overall tonal balance. That's why adding a sub makes so much sense, as you can place the speakers optimally, and put the sub in the best spot for bass. It's a win-win scenario.