SVS SB12-NSD Subwoofer Review Introduction

The SB12-NSD is the smallest subwoofer available in the broad lineup offered by SVS and is a sealed design using the same 12” driver and Sledge amplifier used in the recently reviewed PB12-NSD, but with some tweaks to the limiter and DSP in the amplifier that optimize it for the smaller sealed enclosure. The SB12-NSD also happens to be the most frugal way to own one of SVS’s current offerings with an as delivered price of $649. Purchasing a pair together nets you a nice discount and a total cost of $1149 shipped for 2 units. Having recently reviewed both SVS’s top of the line PB13-Ultra and their entry level bass reflex offering the PB12-NSD and been thoroughly impressed with the quality and preformance of both units, I was anxious to sample their entry level sealed alignment subwoofer to say the least..

Unpacking and Initial Thoughts

After having numerous 100, 200 and yes even 300+ lb subwoofers delivered to my home over the past couple of years my lower back heaved a big sigh of relief when the pint sized box containing the SB12-NSD arrived with a shipping weight of less than 50lbs. Yet despite the light weight and compact box the SB12-NSD’s packaging was robust, well thought out and should protect the unit from everything other than a catastrophic mishap during shipping. Unpacking was a simple matter of a few minutes of time and easily accomplished by one person of even limited physicality. Contained within the box are the usual items: the SB12-NSD in its protective bag, the grill also in its own protective bag, the power cord, quick start guide, etc. SVS has opted to offer the owners manuals online for download instead of providing a paper copy.

Once unboxed and revealed in all its glory the SB12-NSD is a very compact unit amounting to what is basically a 14” cube, not counting the signature SVS curved steel grille which does add about 2” to the overall depth. While not the absolute smallest unit I have reviewed, it is close. Additionally the weight of the SB12-NSD is only 35lbs so unpacking and moving it into position are a piece of cake. The finish on the review unit was SVS’s basic charcoal black vinyl which has a dark matte look with just a little texture to it. It is a clean but functional looking finish that disappears into a dimly lit room easily. The SB12-NSD is also available in a piano gloss black finish for a $30 up charge for those that want a little more pizzazz in the looks department. With its diminutive size, the curved grille attached and the slight rounding to the cabinet corners the SB12-NSD should rate high on the S.A.F. (Spousal Acceptance Factor) scale. I liked its modern yet functional look as did a few of my friends that I showed it to. The fit, finish and parts quality of the SB12-NSD appeared commensurate with what I have come to expect from SVS. In other words excellent.

Design Overview

The SB12-NSD is a sealed system utilizing a single 12” nominal driver forward firing on the front panel. Power and control for the system comes from an SVS proprietary Sledge plate amplifier rated at 400 watts continuous into a nominally 4ohm load. This is the same amplifier used with the previously reviewed PB12-NSD but with the DSP and protection settings optimized for the SB12-NSD instead.

Removing the SB12-NSD driver from the enclosure revealed it to be identical to the 12” driver used in the PB12-NSD which as mentioned in that models earlier review, is a high quality drive unit developed using FEA analysis. The driver is built upon a powder coated, open design, cast aluminum frame to which is attached a rubber half roll surround and a moderate diameter Nomex linear spider with sewn in voice coil leads. The cone is a lightweight aluminum with a composite dust cap embossed with the SVS logo. The voice coil is a 2” nominal diameter with a high temperature former material to better cope with high power and the motor system is completed by double stack of ferrite slugs of about 5.5” in diameter and about ¾” thickness each. A vented pole piece and a heavily bumped back plate round out the package and prevent mechanical bottoming of the former. Additionally there are two aluminum shorting rings in the motor to control and lower inductance.

The Sledge amplifier is listed as providing 400 watts continuous and as being a class D switch mode type having very high efficiency. This amplifier is a more stripped down version of the STA-1000D from the PB13-Ultra having the basic: Gain, phase, auto/on switch, RCA style inputs and daisy chain output connections as seen in the PB13-Ultra but without all of the extra bells and whistles like balanced XLR inputs, parametric EQ ability and minus 600 extra watts of muscle. Otherwise the construction quality seemed to be similar. A couple of small aluminum heat sinks are in evidence internally in addition to the heat sinking surface provided by the faceplate but in testing and use the amplifier never got any more than warm to the touch even with long duration test signals indicating that the efficiency is indeed very high.

The small enclosure of the SB12-NSD is constructed of 1” MDF material and despite lacking any cross panel bracing internally is inert and dead offering no appreciable resonance or vibration during listening, measurement testing or with the highly scientific knuckle rap test. This is due to a couple of things. First the panel material is thick and secondly the interior is generously lined with poly batting on four of the six enclosure panels. Even more important is the simple fact that the panels are very small which makes them very stiff already. Small enclosures with short panels such as this simply do not need heavy internal bracing like larger subwoofers do. This is why you see internal bracing extensively used in the much larger SVS PB13-Ultra and not here.

The black vinyl wrap used on the review unit was applied well and with the subtly rounded corners give the SB12-NSD an understated look. The grille secures firmly to the front of the enclosure with tabs that seem to be a little more durable than the typical fare used on most speaker grilles and the driver and amplifier are both nicely countersunk into their respective panels. The end result is visually pleasing and unobtrusive subwoofer. I can only imagine that the piano gloss finish enhances the visual appeal of the SB12-NSD that much more. The quality of construction, finishing and components is very good for this price bracket.