TEST: QSC KS118

 What do you want from a transportable subwoofer for live use? In addition to an opulent sound pressure level in the low bass range, it should be very well manufactured, robust in every respect and, as the order already mentioned, it must be transportable and, if possible, can be handled by only one person. QSC is launching the QSC KS118 for exactly this purpose, so let's take a look at how it performs in this regard.

The construction of the QSC KS118

No matter how hard you try in the design department of a manufacturer, the tiresome triumvirate of sound - robustness - weight simply cannot be fooled. The fact that, thanks to Class D technology, it is now possible to design active sound reinforcement systems in the kilowatt range with an ease that was undreamed of even years ago would have been unimaginable in the days of passive systems. The power amplifier issue is thus off the table, but the moving air cannot be subjected to any technical trickery.

Thus, among other things, it is the speaker system, but above all the road construction, that still wants to be moved and should also provide the necessary counterweight for a vibration-free reproduction. To say it right up front, QSC has done a great job here. Although a weight of 49 kg is not to be thought of carrying for a 1-man company, QSC has installed 4 high-quality, smooth-running heavy-duty transport rollers on the back of the cabinet, which do a very good job once you have balanced the woofer on the back. Incidentally, the QSC KS118 is the successor to the KW181, which in turn has enjoyed a good reputation in the scene for many years.

Mind you, the woofer first has to be balanced on the back and who doesn't know the problem that the rollers develop a life of their own from an angle of about 45 degrees and if they are not somehow braked, "run away" from the bending point. However, QSC can't do anything about this; unfortunately, it can't be avoided. In general, everything possible has been done with the QSC KS118 to ensure that the product arrives safely at its destination, no matter how it is handled. Especially if you order the very high-quality protective cover right away, which in addition to a pocket for power or signal cables over several Velcro straps not only the cover itself, but also on top of stored products, such as the satellites, to attach knows... Logically, these roles automatically make the QSC KS118 a rolling cart.

The cabinet of the QSC KS118 is constructed of 18 mm birch plywood, which generally enjoys a good reputation, especially since a large part of the world-famous Marshall 4x12" guitar speakers are also made of this material. The cabinet is covered with a resistant textured lacquer, which should withstand at least rudimentary external influences. As additional protection for the speaker opening, the cabinet is closed from the front with a solid grille. With dimensions of 640 mm x 520 mm x 785 mm, you're already dealing with a full-grown subwoofer in the compact range, which can be moved by one person thanks to the heavy-duty casters, as long as you have the appropriate ramps in the loading area. Lifting the product alone is hopeless.

The QSC KS118 has 4 adjustable feet each on the bottom and one side panel, while the opposite side has analog 4 recesses for daisy chain stacking. Well thought out, well executed. If you now think that mentioning such a matter of course is exaggerated, you should take a look at the competition to see what kind of crude solutions are sometimes expected of the user in this regard.

On the top of the case is an M20 threaded flange that works with all common spacer rods. Of course, QSC also has corresponding rods for the in-house tops in their program.

The electronics of the QSC KS118

With 3.6 KW peak power, we are then already in the range where you can not only hear the bass, but also feel it. To get the most out of the system, an 18-inch long-throw driver works inside the cabinet, offering a frequency response of 35 - 111 Hz at a maximum level of 136 dB.

The system is monitored and controlled by an extensive DSP, which, in addition to various safety circuits, also has a few helpful tools on board. A small but easy to read display navigates through a standard menu, which is self-explanatory and requires no study of the manual.

In terms of crossover, you have the choice between 80 and 100 Hz, depending on which crossover point the satellites offer. Depending on the placement of the woofer in the network, you can set a delay of up to 100 ms, which corresponds to a distance of about 34 meters. Depending on the application, various DSP settings can also be saved and recalled accordingly. Interesting and not self-evident in this range is also the Cardioid Radiation mode, which of course requires at least 2 woofers of this type. Finally, you can activate a DEEP mode, a kind of bass boost that boosts the low frequencies even more.

The QSC KS118 has 2 inputs, both of which have appropriately looped outputs for daisy chain operation. Both inputs are controlled in parallel with an input control, which boosts the input signal up to 10 dB if required. The necessary cooling is provided by a speed-controlled fan, which runs quite quietly. Finally, there is also the On / Off switch and the power plug on the back.

The QSC KS118 in practice

In order to be able to evaluate the QSC KS118 in context, I received a complete setup, consisting of 2 QSC KS118 and two corresponding satellites from QSC plus the distance rods, so that I had a total of almost 11 KW of power available. In the context of this setup, the woofer really left an excellent impression. This woofer can really get very, very loud, but cushions the peaks with a very large headroom in an almost relaxed manner.

It was also interesting that when the crossover frequency was changed from 100 Hz to 80 Hz, the low bass range was reproduced a tick stronger. Not striking, more subtle. In general, the QSC KS118 succeeds again and again, despite the almost ostentatious performance specifications, to complete its task very discreetly in the background, just as one would wish from a subwoofer.

The situation is similar in DEEP mode. Here, too, the system is comparatively discreet, but also leaves no doubt that the boost has been activated. It is truly impressive what the system gets out of just one speaker when optimally tuned.

I fed the system with various test tones and reference recordings. As is almost always the case with audio reproduction, as the volume increased, heavily mastered material tipped over into an aggressive mush at a certain point, while a live recorded drum set banged without any processing whatsoever that it was a joy. Not really new, but always worth a mention.

The preset Cordioid preset is also a great relief when it comes to quickly curbing the notorious booming frequencies behind the subwoofers towards the stage via phase cancellation. Stack or position them next to each other, insert the preset, done. Alternatively, you can of course use the delay for a corresponding noise cancellation by placing two woofers one behind the other, which, as is well known, requires corresponding tables and is always only a compromise in terms of frequency cancellation. For an optimal implementation for the QSC KS118 system, however, you need 3 woofers, 2 front-loaded and one rear-loaded with appropriate phase rotation.

Conclusion

The QSC KS118 is a top class product on the active subwoofer market. The system features sophisticated DSP control, exceptionally high headroom, very good build quality, and high practicality.

You need one person to roll it, 2 people to carry it, and in return you get an excellent woofer that delivers just under 22 KW of bass with, for example, a 2-way cardioid arrangement in front-rear-front alignment. This is enough to provide a club with adequate and ambitious sound. QSC once again shows their great experience in the subwoofer field and has created a worthy successor to the KW181 with the QSC KS118.

Additional Informations:

QSC Audio: Revolutionizing Professional Audio Solutions
Introduction:
QSC Audio, established in 1968, is a leading global manufacturer and innovator in the field of professional audio equipment and solutions. Based in Costa Mesa, California, USA, the company has been at the forefront of developing cutting-edge products that have redefined the audio industry. With a commitment to excellence, innovation, and customer satisfaction, QSC Audio has earned a reputation as a trusted partner for professionals in the sound reinforcement, live performance, and entertainment sectors.

Company History and Evolution:
QSC Audio was founded by Patrick Howe Quilter, Barry Andrews, and John Andrews. The name "QSC" stands for Quilter Sound Company, reflecting the founder's vision to provide high-quality sound solutions. The company initially focused on guitar amplifiers and developed a strong presence in the musical instrument industry. However, as technology evolved and market demands shifted, QSC diversified its product line to include power amplifiers, speakers, digital signal processors, and complete sound systems.

Innovative Products and Technologies:
QSC Audio has consistently pushed the boundaries of audio technology, revolutionizing the industry with its innovative products. The company's flagship product lines include:
Power Amplifiers: QSC's power amplifiers are renowned for their robustness, reliability, and efficiency. The PowerLight series, featuring Class D amplification, significantly reduced the weight and power consumption of amplifiers without compromising performance. This breakthrough technology made QSC a pioneer in the realm of lightweight, high-power amplifiers.

Loudspeakers: QSC's loudspeaker offerings cater to various applications, from portable speakers for small venues to line array systems for large-scale events. The K Series and KW Series are notable examples, designed to deliver exceptional audio quality and versatility.

Digital Signal Processors (DSP): QSC's DSP platforms, like the Q-Sys series, provide comprehensive audio processing and system control. The Q-Sys platform is a flexible and scalable solution, enabling users to manage audio in various environments, from conference rooms to complex live events.
TouchMix Series: The TouchMix digital mixers have gained popularity among musicians, sound engineers, and performers due to their user-friendly interface, powerful processing capabilities, and compact design. These mixers strike a balance between advanced features and ease of use.
Cinema Solutions: QSC has also made significant strides in the cinema industry, providing audio solutions for movie theaters worldwide. Their DCP series of cinema processors and amplifiers have become an industry standard, delivering immersive audio experiences to moviegoers.
Global Reach and Customer Base:

QSC Audio's commitment to innovation, reliability, and superior performance has garnered a loyal customer base worldwide. The company's products are widely used in various industries, including:

Live Sound and Touring: Many renowned artists, bands, and production companies rely on QSC's audio systems for their live performances and touring events.
Installed Sound: QSC provides solutions for various fixed installations, such as houses of worship, conference centers, stadiums, and theme parks.

Corporate and Enterprise: QSC's audio solutions are employed in boardrooms, conference rooms, and meeting spaces to facilitate clear communication and seamless collaboration.
Entertainment and Hospitality: The entertainment industry, including theaters, music venues, hotels, and restaurants, benefits from QSC's audio technology to create immersive and memorable experiences for their patrons.

Commitment to Sustainability and Environmental Responsibility:
As a responsible corporate citizen, QSC Audio emphasizes sustainability and environmental consciousness. The company actively pursues eco-friendly practices throughout its operations, from product design to manufacturing and packaging. QSC aims to minimize its environmental impact by reducing energy consumption, using recyclable materials, and promoting responsible waste management.

Conclusion:
QSC Audio has evolved from its humble beginnings as a guitar amplifier manufacturer to a global leader in the professional audio industry. With its unwavering commitment to innovation, quality, and customer satisfaction, QSC has redefined the way audio technology is utilized in various applications. As the company continues to push the boundaries of audio solutions, it remains a reliable partner for professionals seeking cutting-edge, reliable, and environmentally conscious audio equipment.