The R-115SW is a 75-pound, 15-inch, 400-watt (800 peak) vented subwoofer that offers a frequency response from 18 to 125 Hz +/-3 dB. It’s a sizeable sub, measuring 19.5″ (W) by 21.5″ (H) and 22.3″ deep. Klipsch offers it in one finish, a brushed black-polymer veneer.
Each sub includes a detachable cloth grill, which removes to reveal the 15″ Cerametallic aluminum cone with its signature copper-colored finish. The design employs a slot-shaped, forward-venting tuned port.
The sub’s rear panel sports a rather minimalist set of inputs and controls. There is no speaker-level input, and the R-115SW does not offer audio pass-through with its stereo RCA line-level inputs. One knob adjusts the crossover point, and a second adjusts gain. There is a LFE setting that disables the crossover. It’s clear this sub is for use with a modern AVR offering built-in bass management.
On the back, you’ll also find one toggle switch for phase and another for power. A DIP switch lets you chose between 120V and 240V. Last but not least, the sub includes a WA port that works with the Klipsch WA-2 Wireless Subwoofer Kit to provide a wireless connection
The R-115SW is a big sub that belts out prodigious quantities of bass. I’m confident many people would find the output of a single R-115SW more than adequate for music and movie watching. The sub is especially generous when it comes to doling out bass in the 20-30 Hz region. Whether it’s rattling the rafters reproducing the upright bass on Dawn of Midi’s Dysnomia or disturbing the neighbors by telegraphing the infrasonic percussive soundscapes of Meat Beat Manifesto’s Answers Come in Dreams, the R-115SW delivers a bone-rattling performance in terms of sheer output.
I ran sine-wave sweeps and was able to energize the entire room with one sub. I achieved room lock (that physical sensation you get from the bass) from 18 Hz on up, and with plenty of headroom to spare. However, pipe-organ fans should take note that the ported design means that the response drops off a cliff below 18 Hz.
Sine waves at 20 Hz coming from dual R-115SWs measured 110 dB at my main listening position—enough to make my vision blurry and trigger nausea. Seriously, that’s more bass than I need. However, when I tried to reproduce 16 Hz, the port started chuffing, and there was very little energy. Klipsch’s 18 Hz low-frequency rating appears to be 100% accurate.
I wasn’t able to sense the micro-dynamic nuance I’ve heard from some other subs, such as the GoldenEar ForceField 5 or the JL Audio e112 (review coming soon), but that’s unsurprising, since both those subs have more powerful amplifiers attached to smaller drivers—and cost more. I don’t have measurements, but I’d guess damping factor—the amp’s ability to maintain control of the cone’s movement—comes into play. Nevertheless, neither of those subs offer as much output per dollar as the Klipsch R-115SW.