Subwoofers — SVS Sound PB-4000

The PB-4000 is the ported rectangular subwoofer of the SVS 4000 Series, which the company built with trickle-down technology from its 16-Ultra line. SVS has since retired it and now directs buyers to the PB-3000 or to the 17-Ultra R|Evolution Series. Its final listing showed USD 1,899.99 against a regular USD 2,399.99, with Premium Black Ash and Piano Gloss Black finishes.

Key specs that matter

One front-firing 13.5-inch driver is matched to the Sledge STA-1200D amplifier, which delivers 1,200 watts RMS continuous and over 4,000 watts peak. Three port tuning modes give three rated responses within 3 dB - 13 to 200 Hz in extended mode, 16 to 200 Hz in standard mode and 18 to 200 Hz sealed. The cabinet stands 59.5 cm high and 52 cm wide, with a depth of 70.4 cm bare or 76.3 cm behind the curved grille, and it weighs 69.5 kg.

Engineering and use context

SVS supplies three foam plugs for the three front-firing 3.5-inch ports, and the DSP loads a matching response curve for each mode, in effect giving three subwoofers in one box. The driver alone weighs 22.5 kg, of which 20.1 kg is motor, and uses an underhung layout with 53 mm Xmax and 91.6 mm Xmech. Its 3-inch voice coil uses eight layers of edge-wound aluminium flat wire, two toroidal ferrite magnets supply the field, and a copper shorting ring, a cast aluminium basket, a paper-composite cone with glass fibre dust cap and a parabolic SBR surround complete it. The Class D amplifier uses discrete 32 A, 600 V MOSFETs and active power factor correction, which holds the supply at 360 V DC on mains from 100 to 240 V and lets full output come from a standard 15 A circuit, while an isolated input stage guards against ground loop hum. The front baffle is double-thickness MDF of about 5 cm backed by internal bracing and insulation. An 8-digit dimmable blue LED display sits inlaid in the front, an IR remote is included, and the SVS app handles volume, low pass, phase, polarity, room gain, port mode, three EQ bands and three presets.

Pairing

The rear panel carries stereo XLR and RCA connections for input and pass-through, each at 22 kilohm, so it can be fed from a home cinema processor or from a studio-style balanced preamp. Auto-on and a 3-12 V trigger are provided. Standby consumption is 0.5 W, and a heavy-duty 1.8 m power cord comes in the box together with elastomer feet.

Alternatives

The SVS PB17-Ultra R|Evolution is the ported model that SVS now recommends in place of the retired PB-4000.