Although many of our readers lean toward high-performance, sports-oriented vehicles, a lot of us also enjoy having a truck for hauling parts, towing other toys and simply for daily driving when the weather sucks.
Of course, we all need good audio in our trucks as well, but sometimes struggle with a lack of space for a good subwoofer system. That’s where the SWT series of woofers from Alpine comes in. The SWT-10S2 and SWT-10S4 10-inch woofers are designed to install and provide great bass performance in very small spaces. As you may have already deduced from the model numbers, the woofer is available in either two- or four-ohm single coil versions. The woofers are rated to handle up to 350 watts of continuous power, and sell for $269 in Canada, and around $230 in the US.
The Alpine SWT woofers are shallow-mount woofers, requiring only 4.2 inches of mounting depth, thanks to the “Airflow” bottom plate design that requires zero clearance between the woofer and the inside of the enclosure. To accomplish this, a series of five wide slots are cast into the bottom plate, surrounding the rear vent opening of the woofer and permitting air to flow through, even when mounted with no clearance. Such a shallow mounting depth also means that the woofer can fit under the seats of many trucks, thus retaining maximum cargo space.
According to Alpine, the woofer can be used in either sealed or vented enclosures, with the vented style being preferred if room is available. Acceptable sealed enclosure volumes range from 0.35 to 0.8 cubic feet, with the optimal being around 0.47 cubic feet. The recommended vented enclosures range from 0.75 to 1.24 cubic feet, with the latter being optimum. When using a vented design, Alpine suggests tuning the enclosure to approximately 31 Hz.
The SWT-10S2 is built in a heavy gauge stamped steel basket, supporting a 4.27-lb. ferrite motor covered with a rubber boot. The magnetic energy drives a four-layer, 2.5-inch EISV copper coil, wound on an aluminum former. The coil assembly is located and suspended by a progressive type Nomex spider, which includes woven tinsel leads for improved reliability and elimination of lead slap under high excursion conditions. This mechanism drives a pressed pulp/Kevlar cone, anchored to the outer basket diameter with Alpine's patented multi-roll High Amplitude Multi Roll (HAMR) profile polyurethane foam surround. The HAMR profile is all new on this woofer, as is the polyurethane foam as the surround material. These changes provide improvements in damping cone edge reflections, increased sensitivity and reduced mass. X-max (one direction) is 11 mm, giving this woofer almost one full inch of excursion capability.
It's a good looking unit, using a smooth inverted dust cap and a well-executed gasket system that includes a concealed mounting system.
The typical nickel-plated spring-loaded speaker terminals will accept eight-gauge cables.
Just as you should never judge a book by its cover, you should never judge a woofer system by the space it requires. I evaluate this woofer in the recommended 1.24-cubic foot vented enclosure, and I'm immediately impressed with its performance. Delivering deep, authoritative bass, the shallow Alpine quickly proves its mettle. Whether you like 50 Cent or Bach, Brooks & Dunn or Nirvana, this system provides you with a clean, very musical bottom end. The bass output from the system is surprisingly good and has a natural timbre. Kick drum and tympani are well defined with nice attack and definition of the stick striking the drum head. Low notes from an acoustic bass sound clean and retain the instruments' natural tone and resonance.
Overall, the Alpine system simply works and, given its size, the sonic performance is formidable. Only when it's pushed well beyond its 350 watt power rating do I get it to complain, but only minimally. Nice job, fellas.
ON THE BENCH
On the test bench, I fire up my trusty Klippel analyzer and measure the woofer parameters. My numbers are a bit different than the published specs in the manual, but that might be attributed to their sample undergoing a more extensive break-in than my schedule allowed. In any case, the performance of the woofer is certainly excellent in the recommended enclosure, so custom enclosure designs won’t be required. Simply use the factories suggested designs and you’ll be pleased.
The Alpine SWT-10S2 woofer is a great choice for a great sounding woofer that can work in restricted space applications. Its flexibility in shallow applications, overall musicality and great low frequency output make it worth every penny. Go find one at your local Alpine dealer and hear it for yourself! www.alpine-usa.com