Update: Review posted here

According to SVS Sound, the recently announced 16-Ultra series subwoofers represent the most important product introduction in the company's history. For this reason, I am honored that the company chose AVS Forum to preview and review the largest and most powerful subwoofer the company has ever built, the PB16-Ultra ($2500).

This is an exclusive, first to review situation—you won't be seeing any other threads about an actual PB16-Ultra for a couple more weeks when they start to ship. Therefore, I did not want to waste any time getting this blog thread started.

The PB16-Ultra arrived on Monday October 31, 2016 by freight. My cat Kirk is curious. Photo by Mark Henninger
The PB16-Ultra Features a 16-inch driver with an 8-inch edge wound voice coil capable of handling the amplifier's 1500 watts of continuous output (5000+ watts peak). SVS says STA-1500D amplifier used in the sub is conservatively rated, and offers superior performance to other class-D designs thanks to the use of discrete MOSFET output. The cone is made of fiberglass resin composite, and the company says that the four toroidal ferrite magnets that make up the motor are the heaviest ever used in a subwoofer.
Please join me in this adventure. The purpose of this blog is to make the review process more transparent and democratic. It's about more than just providing a window into the process, it's a way for you to help make AVS Forum reviews better. I learned much of what I know about subs from other AVS Forum members and have great respect for the community here. The final review that emerges from this blog will benefit from crowd-sourced knowledge and feedback, which is what AVS Forum is all about. I seek your suggestions and will participate in an ongoing dialog, so that by the time these beasts ship, we'll all have a better understanding of this amazing bass-making machine.
Preparing for the unboxing. Photo by Mark Henninger
11/02/2016 - Unboxing

Today, with the help of my friend Jude, I unpacked the PB16-Ultra. It is not at all difficult thanks to the thoughtful design of the packaging, but it is a two-person job because the sub itself weighs over 170 pounds. A bit of trivia regarding the background music in the Unboxing video—that's a track I composed explicitly for the folks I met in the DIY Speakers and Subs forum called "
Dub[/URL] ," and it's free to download . I produced it explicitly to serve as subwoofer torture track, it contains ultra-low, clean bass notes. You absolutely do need a sub like this new Ultra to experience it properly.
Unboxing the PB16-Ultra. Video by Mark Henninger.
If you are familiar with the SB13-Ultra, the following photo should offer a real sense of scale. The PB16-Ultra is huge, so make sure you plan out where you are going to put it. In my case, the only viable choice was the front right corner of the room. Yes, that's a JL Audio Fathom F112 in the background.
The SVS PB16-Ultra sub next to a SB13-Ultra. Photo by Mark Henninger
My friend Jude (on the left) and I pose with the just-unboxed PB16-Ultra. Photo by Mark Henninger.
So far today, just moderate-level listening, have not EQ'd anything yet, or even installed the control app. Regardless, the PB16-Ultra slotted into my system very well, I chose the subwoofer levels "to taste" and am curious what a graph of that measurement will look like. From a purely subjective standpoint it dwarfs the SB13-Ultra I also have on-hand, yes in terms of physical size but also in terms of capability, especially down low.

What really impresses me is how well dialed-in the amp's limiter appears to be. You can push the driver to legitimately scary excursion levels, seemingly on the edge of what's mechanically possible, and yet the sub won't self-destruct if you push it further. This a great thing, most manufacturers err on the side of caution resulting in tepid infrasonic output, despite whatever specifications they list. I'm not seeing that here. I will not be performing CEA-2010 measurements although I understand someone else is doing that, so those number will exist soon enough. But anecdotally, just messing with sine waves and other bass tones, it's clear this sub's designers have found the Goldilocks zone for the amp and the driver and the DSP.

One really good sign is the PB16-Ultra has not problem handling the ultra-deep bass tones in the tracks I composed explicitly with the DIY crowd here on AVS Forum in mind. I'm particularly thrilled with how it handled "
of the Dub King[/URL] ." Now I just have to go find and fix all the rattles in my room that this sub has uncovered.

Meanwhile, "
" provides lots of fuzzy, deep, yet audible bass notes with and occasional tones that drops out from under you. Back when I composed these deep bass tracks, I built a DIY system with four subs tuned to 14 hz, in order to master them properly. The PB16-Ultra is the first commercial sub I have reviewed whereby one sub can properly reproduce everything I put into those tracks. Indeed, it's been so long since I heard them played right, I almost forgot some of the nuances I included. Check out the rumble near the beginning of "
" for an example. If your room/house is starts shaking right away, despite the fact you can't hear any bass, then you're golden.

11/05/2016 Update

Eventually I plan to use the PB16-Ultra in conjunction with an SVS Prime Elevation speaker system SVS was kind enough to send. However, this weekend is all about getting it working in a high-performance two-channel system. With power and processing coming courtesy of a Classé Sigma SSP and AMP5, and a pair of PSB Imagine T3 towers handling everything but the last couple octaves, it's a rig that can accommodate a sub as powerful yet refined as the PB16-Ultra.

The Sigma SSP offers customizable bass management, with options that include setting a crossover point in 10 Hz increments from 40 Hz up to 140 Hz, and the choice of a 12 dB/octave or 24 dB/octave slope. With six memory slots for customized configurations, it makes it easy to try out and quickly compare different settings. Meanwhile, the Imagine T3 towers are exceptional speakers that out-spec SVS's own Ultra towers (more sensitive, play deeper, handle more power, cost a lot more) and happen to be an incredible partner for experiencing the PB16-Ultra.

Three days of listening with no EQ, no adjustment aside from setting levels and the quality of the bass is so high there's little motivation to do anything. I'm using the "music" preset on the sub and it seems like it's really well-suited to a plug-and-play install—this is not a sub you have to wrestle into sounding good.

11/07/2016 Update

Initial measurements were very exciting. I've got tons of room gain, at 19 Hz I measured 115 dB at my listening position with all three ports in use. The MLP is 10 feet away from the front of the sub, which in turn is located in the front right corner of the room. That's not necessarily a peak measurement, it's just the loudest sweep I dared measure while my neighbors are home.

Tons of output at 20 Hz when using all three ports.

Measurements from the MLP, sealed vs. two ports vs. three ports.
After getting a taste of the SVS control app I can confidently say it's the best way to configure a subwoofer. Upon first launch, it found the PB16-Ultra right away and connected without incident. First time users can opt to go through a step by step demo that encompasses all of the app's features.

The app's controls are clear and comprehensive; I look forward to dialing-in the sub with the help of REW...

I activated Room Gain Compensation, 12 dB slope, centered on 25 Hz. It flattened out the response like a charm. Output is freaking insane, and on the final measurement (115 dB at the MLP) one of the pictures on my wall came crashing down, which is a first. Now I have to work on reducing the effect of that null; normally I'd throw another sub at the problem but in this case there's enough spare capacity coming from the sub that I plan to shrink it with judicious use of PEQ.
Room gain compensation flattened out the unruly response in the deep bass zone. The sub hits 115 dB, measured at the MLP.
With room gain comp. applied, the app made short work of using the parametric EQ function to create a nice blend, as measured from the MLP. About 20 minutes worth of sweeps for this result:
24 dB/octave smoothing shows how impressively linear the PB16-Ultra's calibrated output can be, once dialed in.
Here's what the PEQ did to the sub on its own, versus no PEQ:

Time to do some listening... Dirac Live calibration coming soon.

I will update this post continuously, so stay tuned.