SVS SB16-Ultra Subwoofer Reviewed

Maybe you will wonder that why SVS, long one of the top names in subwoofers, didn’t offer a sub with a driver bigger than 13 inches. Sure, smaller cones have a rep for delivering a more tuneful sound, but many judge a sub solely on the size of its woofer. With the new $1,999 sealed-enclosure SB16-Ultra reviewed here–and its ported brother, the $2,499 PB16-Ultra–SVS can now score as many points on size as it always has on quality. Each sub incorporates a single 16-inch woofer, driven by a high-efficiency Class D amp rated at 1,500 watts continuous power, 5,000 watts peak power.

The size of the voice coil diameter of the driver on these subs is eight inches. Normally a four-inch voice coil is considered impressive. The voice coil is the wire coil that the electrical signal from the amp passes through. It’s wound on a cylindrical former and attached to the back of the cone. The force from the voice coil pushes and pulls on the cone to make sound. In drivers with smaller voice coils, almost all of the cone surface sits between where the voice coil is attached to the cone and where the cone is attached to the surround (which is affixed to the driver’s frame). There’s nothing to support the cone in this area, and with so much of its surface unsupported, the cone is left to flex and, if pushed hard enough, to distort. In the SB16-Ultra and PB16-Ultra, the voice coil is attached at the approximate midpoint of the cone, making the cone stiffer and less prone to distortion.

Here are the other unusual feature on these subs is the new SVS smartphone control app. The app lets you set the usual functions, such as the low-pass filter (crossover) point, phase and volume, and it also offers a parametric EQ feature that lets you adjust the sub’s response to compensate for the effects of room acoustics. The EQ offers three adjustment bands. Each can be set for a center frequency between 20 and 200 Hz in one-Hz increments; boost or cut in a range of +6/-12 dB; and a Q (bandwidth) of 0.2 to 10.

Augmenting the EQ is a room gain compensation feature, which reduces buildup of low-frequency energy in small rooms. It reduces bass at either -6 or -12 dB per octave, below a frequency adjustable from 25 to 40 Hz. There are also Music and Movie modes: the Music mode is basically flat response, and the Movie mode introduces a mild boost in the midbass.

There’s no automatic function. You set these controls manually, preferably with the help of an audio spectrum analyzer–a tool that every audio enthusiast should have. Fortunately, these analyzers now cost very little. All you need is a Dayton Audio UMM-6 measurement microphone (under $100) and a PC running the free Room EQ Wizard software package. You could cheap out with a spectrum analyzer smartphone app such as Audio Tool, but this isn’t as accurate and doesn’t provide a large-enough display for fine adjustments.

All of the functions available through the app can also be adjusted through the sub’s angled front panel. A credit-card-sized remote controls volume, accesses the front-panel menu system for adjustments, allows selection of three presets, and turns the front-panel display on and off.

The SB16-Ultra is a roughly 20-inch cube, so it isn’t large compared with many of the ported subs I’ve reviewed. However, its beefy driver and double-thickness MDF enclosure make it heavy: 122 pounds. It includes XLR and RCA line-level inputs and outputs, although no high-pass filtering is available for the outputs. So, if you want to filter the bass out of the main speakers, you’ll need to use a surround processor/receiver or a stereo preamp with a subwoofer crossover built in.

As of this writing, SVS is offering $200 off if you buy a pair of SB16-Ultra subs.

The Hookup
As usual, I put the SB16-Ultra in my room’s subwoofer sweet spot, the place where most subs tend to sound best from my usual listening position. (In my room, that’s just to the left of the right-channel speaker.) I used two different systems. The first was a two-channel system using a Classé CP-800 preamp/DAC and a Classé CA-2300 stereo amp, alternating between Revel Concerta2 F36 and MarkAudio-SOTA Viotti One speakers, connected using Wireworld Eclipse 7 interconnect and speaker cables. The second was a home theater system using a Sony STR-ZA5000ES AV receiver and Sunfire CRM-2 and CRM-2BIP speakers. Subwoofer crossover points were 80 Hz for the stereo system and 100 Hz for the home theater system.

Once you download and install the SVS app, adjusting the sub’s functions is easy and intuitive. I played pink noise through the subwoofer and used TrueRTA software with an Earthworks M30 measurement microphone and an M-Audio Mobile Pre USB interface to measure the bass response in my listening chair. With about five minutes of adjustment, using the parametric EQ and room gain compensation, I had the response pretty close to flat. If you’re not yet familiar with the way parametric EQs work, the process will take much longer, but it’s fun because you can see the effects of your adjustments immediately.

I later experimented with the room gain compensation adjustment by ear to get the low-frequency response exactly where I liked it. It is possible to adjust all of these controls by ear; but, unless you’re very good at identifying the sounds of the different bass bands, you’re flying blind if you make these adjustments without using a decent spectrum analyzer.

Performance
I’ve heard almost all of the top subwoofers currently on the market. The SB16-Ultra sounds like none of them. It’s almost in a whole different category of low-frequency sound.

The deep bass notes that begin Kanye West’s “Love Lockdown” tend to distort at least a little bit through almost any system when played at a moderately loud volume. With the SB16-Ultra, I could hear no distortion at all, even with the system cranked to the limits of what the main speakers could handle. It’s the first time I’ve heard the bass tones fill the room on this tune, pressurizing the entire space with intense low-frequency energy. Normally, a subwoofer would distort on these tones, producing higher-frequency distortion harmonics that draw my attention to the subwoofer. But with this sub, I felt truly enveloped, and I got the feeling that I was hearing the tune the “right” way for the first time. I also noted more subtlety in the bass tones. I assume they’re generated electronically, through synthesis or sampling, then heavily processed to create the desired effect; however, with the SB16-Ultra, I could hear subtleties that gave the bass a more natural tone, somewhat like that of a Japanese taiko drum.