QSC K Series Loudspeakers, Engineering Preview

by Ron Simonson, PE


I just came back from our private pre-release preview of the new QSC “K” series portable powered loudspeakers, consisting of the K8, K10 and K12. The “K” series sound simply incredible! These speakers are the result of solid engineering principles and innovative design and manufacturing techniques.


An engineer I’ve known and respected for over 20 years, Mark Engebretson, QSC’s VP of R&D, has come up with a winning portable loudspeaker in the “K” series. Mark is a true acoustics engineer who understands the behavior of loudspeakers in the real world and how to apply both physics and digital signal processing to radically improve the standard portable 2-way loudspeaker. Mark started out by making sure that the “K” series speakers would have consistent power response through the crossover frequencies. Consistent power response means these speakers not only sound great when the speaker is aimed right at the listener, but they also sound great off-axis. The “K” series has the sound of a high quality recording studio monitor.


One of the unique design choices that QSC has made in developing this speaker, and the factor that gives it consistent power response, is matching the coverage angle of the high frequency to the size of the low frequency driver. Yes, low frequency drivers actually do have coverage angles. Most manufacturers don’t talk about this, but its simple physics. The larger the low frequency driver, say a 12″ or 15″ LF, the narrower the coverage angle of that speaker will become at the crossover frequency. Matching a 15″ LF driver with the typical 100 degree HF horn results in mis-matched power response through crossover, but that’s exactly the coverage angles will find in a typical 15″, 2-way speaker.


What QSC has done in the “K” series is to perfectly match the size of the LF driver to the coverage pattern of the HF horn. The result? Perfect power response! The benefit? Great sound!


Of course, in order to get low frequency output from a smaller LF driver, other improvements had to be made. Consistent with Mark E’s physics and acoustics expertise, there is no “smoke and mirrors” approach here, just solid engineering.


First, QSC made the box enclosing the speakers stronger and more rigid than competitive loudspeakers. That means greater mechanical efficiency for more output. Second, they beefed up the LF drivers to handle more power and dissipate more heat. That means more acoustical output than similar 2-way systems. Finally, they put in a 1000W amplifier to drive those ”hot rodded” LF drivers to an output level that exceeds other 2-way systems with similar size drivers. In fact, the K12, with a 12″ LF driver exceeds the output capacity of many competitive 15″ 2-way speakers. So now you have the first light weight, compact 12″ 2-way speaker on the market capable of blowing away some competitive 15″ 2-way systems in both sound quality and output! At the listening preview, one of our guys that mixes at his own church was asking where the larger speaker was. He couldn’t believe all of that bass was coming from a K10!


As they say on TV, wait…there’s more. Not content to have just a great sounding, light-weight speaker system, QSC set out to create a new standard in sound quality in the portable loudspeaker segment. Using very advanced Digital Signal Processing (DSP), built into every “K” series loudspeaker, QSC analyzed and corrected scores of small aberrations in phase response that are present in any loudspeaker design. This final step is what gives every “K” series loudspeaker the “studio monitor” sound that produces clear vocals and authentic instrument reinforcement. Not only is this very “techy” stuff, it’s not easy nor cheap. But, believe me, you can hear the difference!


All of these design techniques are based upon fundamental physics which speaker designers have known about for years. Why hasn’t someone else done this before? The answer is that they have! In very expensive and exotic speakers. Here’s the real QSC breakthrough. Bringing this fundamentally sound, high tech method of building speakers into a series of speakers that sells for as little as $650!


Don’t ask me how; QSC has developed a way to build all of this quality and technology into speakers selling between $650 and $799. That’s no more than you would pay for a standard powered 2-way speaker. Of course, the “K” series has the typical high quality handles, angled floor feet and built-in rigging points that other speakers now have in this price range, but QSC offers even more. Take a look at the back panel. You can even hook up a simple remote volume control for installations!” These speakers are packed with features, technology and great sound, but you pay no more than you would for other good 2-way speakers.


I’ve heard these speakers. I can tell you that the “K” series speakers are like having recording studio monitor sound in a lightweight and compact package you can take to any gig or rig to provide an easy to hang permanent system in small and medium size rooms. You can hear them for yourself through our “Try It Free” program. We’ll ship a pair of K12’s to you to use in your own church, youth room or gathering space. Just give us a call at 1.800.426.8664. Or, you may simply want to order them right now. We offer a 30 day satisfaction guarantee, so you’re completely covered if these speakers aren’t exactly what you expected. I’m guessing that these speakers will be very popular and will be hard to get for several months. CCI Solutions has a priority shipment coming in and you can be one of the first on the list to get a pair by just giving us a call today! Learn more about the QSC K Series


Ron Simonson, P.E.

President & CEO

CCI Solutions