
QSC KS118 Subwoofer
The new QSC KS118 subwoofer can generate a maximum SPL of 136 dB (at 1 meter). Add a second KS118, and you're working with over 140 dB max SPL from a very compact system. DEEP mode sacrifices a few dB of output for lower lows, which may be an acceptable trade-off in certain settings.
QSC's new KS118 self-powered 18-inch subwoofer joins two compact 12-inch subwoofers to round out the KS line. The KS118 is designed to both replace and one-up the older KW181 subwoofer, re-orienting the cabinet and doubling the power output along the way. The KS118 also adds a control panel and display to access its expanded processing features.
Whereas the 12-inch KS-series subs use bandpass enclosures to eliminate unwanted high frequencies, the KS118 uses a traditional front-mounted driver and electronic filtering to limit its frequency response. For the KS118, that frequency response is about 40-100 Hz at -6 dB, or 35-110 Hz at a more-forgiving -10 dB point.
One KS118 setting worthy of a double-take is cardioid mode. That's right--a pair of KS118s can work together to direct bass energy in a cardioid pattern.
The KS118 also has a DEEP mode which "boosts the low frequency extension below 60 Hz", but there's no indication how far it extends the low frequencies. We look forward to checking that one by ear. Technically, the KS series doesn't extend far into the bottom octave of the human hearing range, but few subwoofers do. It takes tremendous amounts of power to operate down below 30 Hz with common drivers, and the 40 Hz range does a fine job of rattling seats and internal organs.
Amplifier power of the KS118 is stated at 3,600 watts peak and around 2,000 watts continuous. That's a generous amount of power, and it allows the subwoofer to generate a maximum SPL of 136 dB (at 1 meter). Add a second KS118, and you're working with over 140 dB max SPL from a very compact system. DEEP mode sacrifices a few dB of output for lower lows, which may be an acceptable trade-off in certain settings.
In keeping with the processors-everywhere trend, the KS118 has an internal interface to manage its on-board DSP. This interface sits between the wheels on the back of the KS118, wisely guarded from damage by a pair of sturdy skid strips. Two buttons a knob allows you to step through the pages of a simple menu where you can control crossover, delay, DEEP mode and more. You can even store scenes for install recall of all system settings.
One KS118 setting worthy of a double-take is cardioid mode. That's right--a pair of KS118s can work together to direct bass energy in a cardioid pattern. The subs must be placed next to each other in one of three configurations, with one pointing forward and one pointing backwards. Select FORWARD and REAR on the subs respectively, and DSP trickery will reduce SPL by as much as 15 dB behind the cabinets. This is stated to tighten up low-bass response in certain venues, something we look forward to testing. It's worth noting that smaller sibling KS212 is a cardioid sub as well, with one forward- and one rear-firing driver in a single enclosure.
The KS118 weighs just over 100 lbs, and has a few features designed to make it easier to wrangle. Large, low-noise casters are permanently attached to the bottom of the speaker. Two inset handles should make it a simple two-person operation to lift. The top of the KS118 has an M20 threaded socket that accepts an optional pole for mounting an upper cabinet. Obviously, QSC would like you to populate that pole with a suitable full-range cabinet, such as the QSC K12.2. The KS118 was not designed to be flown.
The single 18-inch subwoofer has been a workhorse of compact and mobile sound systems for many years. QSC's latest take on this familiar speaker has many intriguing features, including the ability to pair up with a second KS118 for directional bass output. We're eager to put this promising new speaker to the test in the near future.