Brent has been a professional audio journalist since 1989, and has reviewed thousands of audio products over the years. He has served as editor-in-chief of Home Theater and Home Entertainment magazines, contributing technical editor for Sound & Vision magazine, senior editor of Video magazine, and reviews editor of Windows Sources magazine, and he also worked as marketing director for Dolby Laboratories. He's now on staff at Wirecutter.
I've always wondered 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 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.
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.
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.
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.
Holly Cole's recording of the 1970s hit "Good Time Charlie's Got the Blues" from the Night CD starts with a really nice double bass lick that tests the definition of a sub (and the low-frequency output of small subs, but that doesn't apply here). The SB16-Ultra hit the lowest notes on this tune hard and tight, and I could hear both the fullness of the bass and the subtle effects of the bassist's fingering. The sound was something like if you put your ear near to the F-holes on a double bass, which is really the only way to hear all the fullness of the instrument's deepest notes when it's played pizzicato (i.e., plucked, not bowed) without an amp.
When this sub is in the system, one may get a strong urge to play EDM and hip-hop, just because its output is so powerful and its sound so tight. I especially loved hearing the Deadmau5 remix of Medina's "You and I" through this sub. It's a shame that more people can't hear this type of music through the SB16-Ultra because it's really something different. I've never heard a subwoofer this powerful that starts and, perhaps more important, stops so quickly. On "You and I," I heard not a trace of ringing or overhang, which gave the tune a rhythmic precision and power I've never before experienced with either home systems or even with the incredibly powerful sound reinforcement system at the Deadmau5 show I saw a couple of years ago.
The classic submarine movie U-571 is one of my favorite bass tests, especially in the "Face to Face" chapter where the sub confronts a German destroyer. This movie's known for its scenes involving depth charges, but the snippet where the submarine goes under the destroyer and the destroyer's propellers start turning contains more intense deep bass than the depth charges--although most people don't hear it because their systems can't reproduce it cleanly. Like only a couple of other ultra-high-performance subs I've tested, the SB16-Ultra actually seems quieter on this scene than lesser subs do because it doesn't distort significantly, and thus it doesn't produce the higher-frequency distortion harmonics that are much easier to hear than the fundamental bass tones.
Click over to Page Two for more Performance notes, as well as Measurements, The Downside, Comparison & Competiton, and Conclusion...
But the depth charges sounded amazing, too, with a low-frequency component to the explosions I hadn't noticed before. With almost all other subs, you get the punch of the explosion, but with the SB16-Ultra, you also hear the rumble beneath the punch.
The first minute of the Tom Cruise sci-fi vehicle Edge of Tomorrow has become a favorite test of the under-20-Hz muscle of super-subwoofers because it contains loud infrasonic tones that go down to 16 Hz. The SB16-Ultra reproduced even the deepest tones with authority. Of all the movie clips and music recordings I played through the SB16-Ultra, this is the only one with which I managed to get it to distort audibly. So, unless you play the intro of this movie all the time (or the couple of other pieces of content out there with true under-20 Hz tones), you can be confident that you will not hear distortion with this sub.
Bottom line: If you like your bass tight, punchy, and powerful, this sub does it better than anything else I've heard.
Here are the measurements for the SVS SB16-Ultra subwoofer. (Click on the chart to view it in a larger window.)
±3.0 dB from 25 to 192 Hz (Movie mode)
The chart above shows the frequency response of the SB16-Ultra in Movie mode (blue trace) and Music mode (red trace). This is a fairly typical response curve for a sealed-box subwoofer, with a gentle (roughly -12dB) rolloff as the frequency drops below the box/driver resonance. The Music mode's effect is subtle, just a max +3dB boost centered at about 65 Hz.
The CEA-2010 output numbers are impressive. Basically, the SB16-Ultra is a sealed sub with output comparable to that of many large, powerful ported subs. Unfortunately, I don't have measurements of the SB13-Ultra to which I can compare the SB16-Ultra's results, but I do have numbers for the older SB13-Plus, which in my tests delivered an average of 114.1 dB between 40 and 63 Hz, and 103.2 dB between 20 and 31.5 Hz. For the SB16-Ultra, the numbers are 122.4/114.1 dB, respectively. I got basically the same output from Paradigm's 15-inch 2000SW sealed sub, which averaged 122.5/114.4 dB. A top-notch ported sub can surpass both even with a smaller driver: the SVS 13-inch PC13-Ultra averaged 125.8/116.9.
Here's how I did the measurements. I measured frequency response using an Audiomatica Clio FW 10 audio analyzer with the MIC-01 measurement microphone. I close-miked the woofer and smoothed the curve to 1/12th octave. I did CEA-2010A measurements using an Earthworks M30 microphone and M-Audio Mobile Pre USB interface with the CEA-2010 measurement software running on the Wavemetric Igor Pro scientific software package. I took these measurements at two meters peak output. The two sets of measurements I have presented here--CEA-2010A and traditional method--are functionally identical, but the traditional measurement employed by most audio websites and many manufacturers reports results at two-meter RMS equivalent, which is -9 dB lower than CEA-2010A. An L next to the result indicates that the output was dictated by the subwoofer's internal circuitry (i.e., limiter), and not by exceeding the CEA-2010A distortion thresholds. Averages are calculated in pascals. (See this article for more information about CEA-2010.)
I stated before that the SB16-Ultra sounds like no other subwoofer, but that doesn't necessarily mean its sound will suit your tastes. Steely Dan's "Aja," which I've heard through innumerable subwoofers, features an almost perfectly played and dynamically even melodic bass line. With the SB16-Ultra (and the parametric EQ engaged), this line sounds exceptionally even. Every note punches out cleanly at you, and there seems to be no overhang or ringing at all--i.e., when the bass note stops, the driver stops. Technically, it's impressive, but it calls more attention to the bass line and changes the feel of the groove a bit. It's hard to say if this is "right" because this isn't what Steely Dan heard in the studio. An electric bass played through an amp doesn't sound like this; no bass amp I've seen has the output or sophistication of the SB16-Ultra. I would guess that the bass was recorded direct, without an amp, but the bass player and the band members would have heard it through 1970s-era headphones and/or studio monitors that couldn't even approach the SB16-Ultra's muscle.
So it's a different sound, and it's up to you whether or not you like that sound. I know a lot of enthusiasts love that super-punchy, tight bass sound, but I've come to prefer the less-intense experience of a typical ported sub.
As I stated in the measurements, the SB16-Ultra has impressive (probably unprecedented) deep bass performance for a sealed sub, but it still can't deliver that frightening, ultra-low-frequency floor shake that the very best ported subs deliver. When I watched the scene from San Andreas where the Hoover Dam collapses, the SB16-Ultra pounded my chest with notes in the 40-Hz range and was able to reproduce the really deep notes, but it couldn't scare me with subsonic shake the way the SVS PC13-Ultra or Hsu's VTF-15H Mk2 can when used in ported mode.
Comparison and Competition
Most high-end muscle subs are ported. I'm not going to compare them to the SB16-Ultra because, if you're considering a ported sub, you'll almost certainly go for the PB16-Ultra instead--which is much larger and $500 more expensive but will certainly have at least a few dB more output at all frequencies than the SB16-Ultra.
The SB16-Ultra could be compared with the $4,999 Thiel SmartSub 1.12 and the $3,999 Paradigm 2000SW, both sealed designs. The Thiel and Paradigm models are both much more expensive and offer automatic EQ; the Thiel model is also much more beautifully designed and finished. While the Paradigm's output measured about the same as the SB16-Ultra, the Thiel's 12-inch driver can't keep up with either of the larger subs.
Power Sound Audio's $899 15S has a 15-inch driver and, according to Power Sound's published specs, has output comparable to that of the SB16-Ultra, but it has a utilitarian black crinkle finish and a Spartan feature package with no internal EQ.
Probably everyone considering the SB16-Ultra would also consider the $1,599 SB13-Ultra, but the SB16-Ultra looks like the better buy. The SB16-Ultra is a little larger and $400 more, but surely has substantially higher output. The SB13-Ultra does offer parametric EQ, but it has two bands compared to three in the SB16-Ultra, and the center frequencies are fixed in 1/6th-octave steps rather than the 1-Hz steps of the SB16-Ultra. The SB16-Ultra's EQ offers narrower Q settings, which would make it easier to "notch out" narrow peaks. However, the SB13-Ultra has an integral high-pass filter that can filter the bass out of your main speakers, which will come in handy in stereo systems using a preamp with no subwoofer crossover.
The SB16-Ultra is a truly impressive creation that delivers bass reproduction unlike anything else out there. There are many enthusiasts of sealed-box subs (SVS lists the SB13-Ultra as "the most reviewed and top-rated subwoofer in SVS history"), and for them the SB16-Ultra may well be the greatest subwoofer ever made. I expect it will find a following with high-end audio enthusiasts, too, because perhaps more than any other sub I've tested, it is utterly free of the boominess, sloppiness, and distortion that cause many audiophiles to shy away from subs.