SVS SB16-Ultra powered subwoofer

This review began when I ran into Gary Yacoubian, president of SVS, in a crowded hallway at Las Vegas's Venetian Hotel, during the 2016 Consumer Electronics Show. He smiled and introduced himself. "Larry, I enjoyed your review of our SB13-Ultra. If you liked that subwoofer, we have something coming soon that should really interest you. I can't say anything more now."

He'd gotten my attention. But it wasn't until the next year's CES that I learned about SVS's newest and largest subwoofer, the SB16-Ultra, which deploys a 16" driver and a radically different magnet structure, voice-coil design, and control interface. On paper, its greater power and bass extension seemed a good match for the demands of my large listening room. I requested a review sample.

What it is
Yacoubian's infomercial on YouTube about the SB16-Ultra ($1999.99) lists the three design features that enabled SVS to build a subwoofer with so large a cone and still meet the design goals of extended, low-distortion bass output and fast transient response: an 8" edge-wound voice-coil in a new motor, a 1500W RMS (>5kW peak) Sledge amplifier with fully discrete MOSFET output (each output device is rated at 200V and 64A), and control and bass management via a smartphone app.

Yacoubian claims that the SB16-Ultra's 8" voice-coil is the largest used to date in a consumer subwoofer. Most large subs have voice-coils 2" to 4" in diameter that sit inside the permanent magnets; the SB16's 8" coil sits outside the magnets. SVS found so large a coil necessary in order to: avoid the cone flexing and the resultant boomy bass produced in and by subwoofers that have cones 15" to 18" in diameter but voice-coils of only 2" to 4"; maintain linear control over so large a cone; better dissipate heat, which lessens thermal compression and so increases a sub's power handling; provide better centering of the voice-coil, with less tilting during large excursions; and to use the permanent magnets most efficiently. The SB16-Ultra's voice-coil is wound with copper-clad aluminum wire (CCAW); CCAW has a number of advantages: it's lighter than pure copper, for lower moving mass; it's stronger than pure aluminum; has higher electrical conductivity; and is more easily soldered, for more durable and reliable connections.

The SB16-Ultra's voice-coil and four large, toroidal magnets are housed in the motor structure that drives the 16" cone, which has a "premium glass fiber laminated dustcap and reinforced composite cone sub-structure [to] ensure a light, rigid, and neutral radiating surface." The cone is held by a deep basket of die-cast aluminum; the motor alone weighs 56.2 lbs, the entire drive-unit 63.9 lbs.

The SB16's Sledge STA-1500D class-D amplifier is specified to output 1500W RMS, or 5160W peak dynamic. Featuring 64A, 200V MOSFET output devices and a switch-mode power supply, the Sledge delivers significantly more current than the 1000W class-D amplifier used in SVS's SB13-Ultra. The Autostart and Green standby modes can be used to switch the amp on quickly when a signal appears at the input terminals. The equalization and all app settings, including the parametric equalizer, are managed with a 50MHz Analog Devices DSP chip with 56-bit filtering.

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SVS's smartphone app, available free from iTunes and Google Play, uses a bidirectional Bluetooth wireless link that, unlike an infrared signal, doesn't require that the control device and the device controlled be in each other's line of sight. This means that, via the app, the SB16 can be hidden behind a couch and still be fully controlled from the listening position. The app lets you set the sub's phase, polarity, volume, and room-gain compensation (to reduce bass bloat), and even includes a three-band parametric equalizer that controls the strength and width of the filter (the filter's "Q") over a range of 20–200Hz. Settings can be stored in three presets.

The SB16-Ultra's rear panel is uncluttered—most of the controls are included in the user-friendly app. On the rear panel are only the unbalanced (RCA) and balanced (XLR) inputs and outputs, a trigger input, a Power switch, and an IEC inlet for the detachable power cord. The tilted front-panel LCD display, four directional controls, and tiny IR remote can also be used to set up and control the sub. Because the display uses a larger font than other subs I've reviewed, I could more easily read it from my listening seat.

Setup and use
When the SB16-Ultra arrived, I was impressed by its solidity, mass, and size. At 20" high by 19.5" wide by 22.9" deep and 122 lbs, it's 2.6" taller, 2.1" wider, 5.5" deeper, and 30 lbs heavier than the SB13-Ultra, and costs $400 more. SVS's packaging is smart: The SB16 can be slid out of its carton on its packing skids, rather than having to lift it out from the top. After unboxing the sub, I slipped my own Super Sliders under it to protect my hardwood floors, then realized I couldn't move this sub without them.

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My listening room is large—about 25' long by 13' wide, with a semi-cathedral ceiling 12' at its highest—and opens onto a hallway and into the kitchen; the total volume exceeds 5000 cubic feet. On their own, my Quad ESL-989 speakers sound best when they're 8' from my listening seat, 57" from the front wall, and the centers of their front panels are 8' apart and toed in toward me.

Optimally positioning a subwoofer in my room is critical for attaining smooth integration of its output with the Quads' output. I first installed the SB16-Ultra next to the right-channel ESL-989, lining up the subwoofer's driver with the speaker's front panel. I played a brief musical selection and found the sound disjointed—I could easily hear differences in character between sub and satellite speaker. Moving the SB16-Ultra into the room's right front corner, where subwoofers usually go, raised the bass impact and greatly improved the subwoofer's blend with the Quads. This put the sub's cone 10' 8" from my listening chair and 2.5' behind the right Quad's front panel.

SVS's four-page quick-start guide made the rest of the setup process easy. I plugged the SB16's power cord into my Torus Power RM 20 power conditioner. As in many of today's freestanding subwoofers, no high-pass filter is built into the SB16-Ultra to limit the deep-bass signals sent to the main speakers, so I used my Mark Levinson No.526 preamplifier's 80Hz high-pass filter to drive the Quads. When I used my Bryston BP-26 preamp, I also used the high-pass outputs of a JL Audio CR-1 outboard electronic crossover for the Quads. I used balanced interconnects for all connections, and never used SB16's heavy metal grille.

I then downloaded SVS's free app from iTunes to my iPhone 6. Making sure that Bluetooth functions were enabled on the iPhone, I tapped the app. It opened, immediately found the SB16, and paired with it. From my listening seat, I set the sub's low-pass filter to 80Hz, 24dB/octave, and the volume control to –19dB. I then matched the outputs of the sub and the Quad ESL-989s at the crossover frequency, 80Hz. Then, playing a digital track of uncorrelated pink noise, I adjusted the preamplifier's volume until the Quads delivered 75dB at my listening chair, per the SPL meter of Studio Six Digital's AudioTools app. Then I turned off my Mark Levinson No.536 monoblocks, turned on the SB16-Ultra, played the pink-noise track again, and adjusted the sub's volume until it, too, delivered 75dB at my listening seat. Then, with Quads and subs both playing, I confirmed that the SPLs of the pink noise above and below the crossover frequency were equal.

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Fig.1 SVS's SB16-Ultra iPhone control app.

Sound
My first impression of the sound of the SB16-Ultra was tremendous bass solidity and weight—with no muddying of the clarity and transparency of the highs. But there was more improvement to be gained.

As I listened, I found that the soundstage was shallower, and voices had more bass emphasis, than with the Quads run full-range by themselves. In the Kyrie of Ariel Ramirez's Misa Criolla, conducted by José Luis Ocejo (CD, Philips 420 955-2), José Carreras's soft, lyric tenor was now too full and rich, and the separation of his voice from the chorus disappeared. The conga drum that begins "Hotel California," from the Eagles' Hell Freezes Over (CD, Geffen GEFD-24725), was blurred, bloated, and less solid. The final pedal note in organist James Busby's performance of Herbert Howells's Master Tallis's Testament, from the compilation Pipes Rhode Island (CD, Riago 101), failed to pressurize my room.

COMPANY INFO
SVS Inc.
260 Victoria Road
Youngstown,, OH 44515
(877) 626-5623
ARTICLE CONTENTS

COMMENTS
avanti1960's picture

Lacks high level inputs which I have found are critical for audiophile applications.
Driving with high level input (parallel with speaker terminals) sounds better and integrates significantly better when the speakers respond to the amplifier's signal- not the preamplifier signal.
Doubly important when tube amplification is used.

Also of critical importance is a flat, musical frequency response through its useable range. Unfortunately no measurements were provided.

John Atkinson's picture
avanti1960 wrote:
Unfortunately no measurements were provided.

Not sure I understand your point. This review does include in-room measurements.

John Atkinson
Editor, Stereophile

arve's picture

Lacks high level inputs which I have found are critical for audiophile applications.

Using high-level inputs for subwoofers is one of the more fatal mistakes of audio applications:

1. You will most definitely want to place the subwoofer so that speaker-boundary interference is not an issue. This typically involves placing the subwoofer close to the front wall of the room
2. Ideally, you will also want to kill sidewall reflections, which means placing them in the front corner of the room

This means that a subwoofer should typically not be placed at the same distance from the listener as the (front) pair of speakers. For the highest fidelity, it is therefore absolutely critical to have proper bass management, and the simple phase switch/dial on a subwoofer's controls is not nearly enough. You need to be able to apply appropriate delays between the subwoofers and main speakers.

Beyond the obvious issue of time alignment, a high-level input is also completely unable to provide adequate control over crossover frequency: Yes, you may be able to set a low-pass for the sub, but without any control of the high-pass, a subwoofer is a complete and total waste.

avanti1960's picture

to place the sub in the optimum location for best response with high level inputs.
in my experience with critical 2-channel audio the sub integrates better when it sees the amplifier's signal. same signal that the main speakers see. it sounds better and can literally disappear, which is why some of the subwoofer brands that audiophiles love have and recommend the use of high level signal input. connecting to the preamp out tends to make the subwoofer more likely to call attention to itself. in addition, i would never feed my main speakers through yet another crossover or DSP loop. I prefer the setting the sub crossover to the natural acoustic crossover (roll-off point) of the main speakers.
this is an area where home theater and 2-channel audio clearly have different needs and expectations.

JRT's picture

By adding a high pass filter to the mains, you not only reduce excursion at low frequencies (especially important where a woofer unloads to high excursion below the tuning frequency of a bass reflex Helmholtz resonance), but also that high pass on the mains provides poles that affect phase in the sum for a flatter summed response well above the subwoofer's low pass corner frequency, into lower midrange. ...if the crossover is properly executed.

Note that the effected spectrum is into the important telephonic frequency range where hearing is more sensitive to voice quality, and above the Schroeder frequency where Eigentones related to the room's modal response do not dominate the problem set.

At the link below, take a look at Siegfried Linkwitz's write-up, "Issues in loudspeaker design, page 5, section V, Crossover topology issues", and within that look at the graphic labeled "IMPROVED crossover topology" and the associated improvement made to the summed response in the lower midrange and upper bass, above the subwoofer's low pass corner frequency.

http://www.linkwitzlab.com/frontiers_5.htm#V

avanti1960's picture

filtering in the precious signal chain before the main speakers, but i will not be.
many speakers already include a low pass crossover within the design to help with such issues, the ones that do not usually have a very steep, natural roll-off at the F3 frequency, especially if it is a ported design.
measure with RTA software to find that frequency and adjust your subwoofer crossover to correspond with it.

ednazarko's picture

Love that phrase. Consider it stolen.

However, I've found that sometimes pressuring the room can turn musical bass into what I've heard colorfully described as low frequency flatulence. I've struggled with finding that boundary between just pressure or just polite bass with subs. I've had to mess with the subs in the two systems where I have them to find that sweet spot, where the bass is corporeal, but still has pitch. One of my subs has a very sophisticated (for 10 years ago) interface - the UI is very "pong" feeling - that's made it easy to get things right in several different rooms, with several different speakers. And enough different adjustments that you can get it exactly right, or horribly wrong if you don't know what you're doing.

Now I'm very interested in the SVS sub, because the other sub I have, while I've been able to get things right... it took WEEKS of twitchy tweaky adjustments in distances and angles and volumes (with hardly any controls over things like crossover characteristics.) The range of adjustments and app capability is very attractive. I need to find a physical seller I can convince to let me set up an SVS sub with a new set of speakers, so I can get a feel for the process and results.

You mention changing the sub profile for different types of music. The setup process for my older subs is painful enough that I don't even try. But in my AV system, which uses Goldenear Reference towers, I've got several different profiles set up in the AV pre-pro, and it's wonderful. With my headphone setup, ditto - I've got a profile that I call ECM (record label) and another I call "live orchestra recordings," among others. It'd be nice to have that capability in my other systems.

Doctor Fine's picture

One sub is OK I suppose but for deeper separation you really should use a minimum of two.
I use four.
Two SVS 12 inch sealed box subs and two Velodyne 15s.
Setup is to first get my mains sounding their best, then add the 12s and get it to sound its best and then add the 15s and tune them into the array.
Location of the sub voicecoils is best when physically time aligned with the main mid bass/midrange/tweet voice coils BUT in installation where it looks too bulky the big 15s MAY be hidden at the edges of the soundstage and by using a variable phase control they can be integrated nicely.
No idea what the earlier guy was on about as all my phase parametric crossover and other controls are still operable when using speaker level inputs on both my SVS and Velodynes
SVS delivers a high quality product in my experience and I have used the largest Rels, Velodynes and others for professional installs for years.
Sealed box subs are tight sounding and quick.
Ported can get more bass extension.
Yet another reason I use BOTH kinds.
Sub control is mandatory in any case.
Crossover, continuously variable phase control, parametric EQ and of course volume should be considered the minimum you should expect to see on a sub used in a musical system as opposed to a simple theater boomer.
Nice review.

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