Hands-On Review:QSC K Series Powered Speakers
Significantly raising the standard for powered portables
By Jim Gault
Musician’s Friend Staff Writer
Hands-on reviews are fun to do. Who doesn’t like checking out new gear? But they offer the most fun when the gear you have your hands on is especially cool. QSC’s new K Series Powered Speakers are just that. They are exceptionally compact, very high powered, have a number of unique features, and sound fantastic. There are three K Series two-way units—an 8, 10, and 12. Then there’s a dual 12" subwoofer. These are speaker sizes one would equate with monitors, not mains. But that’s before you hear them. They may be small in size and loaded with small speakers, but the woofers have 2" voice-coils (2-1/2" on the K12 and KSUB) and each cab houses a 1,000W power module and a 1-3/4" titanium-diaphragm high-frequency driver. Each model has the same DSP, the same quality components, the same Class D amp, and the same design and control features. Only the woofer and cab sizes differ among models.
There are many small systems out there, but most are not capable of filling rooms or producing pro-quality sound. The K Series speakers are professional all the way: amazingly powerful and their sound is impeccable. Even the smallest is capable of a maximum SPL of 127dB. When I plugged in the K8 and fired it up for the first time, I was blown away. It looked ridiculously small for the volume of sound it was putting out; the sound was almost the same whether I stood five feet in front of it or 30 feet back—very clear, full, and clean. What particularly impressed me was how much low-frequency response was coming from such a small cab, and this was without any help from a subwoofer or even the DEEP switch, which I will tell you about below.
Built-in mixer and EQ presets
All of the K Series two-way cabinets have a two-channel mixer section, something that’s pretty standard for powered speakers these days. It lets you use a single cab as a mini PA system, which can be handy, or as an amp for an acoustic-electric or upright bass. Each channel is equipped with a combi input, both accept line signals, and one is switchable to mic level. There are also RCA inputs for mixing in CD/MP3 sources as well.
QSC has also given the K Series speakers some unique features that are pretty nifty. For example, a back-panel switch lets you choose between a flat EQ and one enhanced for vocals. The latter works really well. It brings up just the right frequencies to accentuate your voice and bring it forward in the mix. The difference is pronounced.
Another switch on the back lets you select Standard or DEEP Modes. I first tried out the DEEP mode on the K8. The cab already had a surprisingly strong low end, but the DEEP switch made it sound as if I had just turned on a subwoofer. It is amazing that an 8" speaker and such a small cab can produce such a massive bottom. It has to do with EQing, for sure, but as QSC explains, the extra-low extension is made possible by high amplifier power combined with DSP limiting of the woofer’s excursion.
Spreading good sound around
The K10 and K12 each add a few dBs of SPL and extend the low end, but the main difference between the cabs is dispersion. The K8 has the widest sound field—105° coverage. The K10 has a narrower dispersion—90°—and the K12 has a 75° coverage pattern. For installed applications, the right choice is pretty simple. If your audience is close to the stage and the room more wide than deep, the K8 is the best choice
Putting it all together
When you add KSUB subwoofers to the K8, K10, or K12, you have a system that kicks big-time butt without crowding the band off the stage or ruining the view. Though the KSUB is larger and heavier than the K12, its deep, narrow shape minimizes the onstage footprint. It weighs 74 pounds, but handles built in the right places and heavy-duty casters help you load in easily. It comes with a pole and threaded socket so the two-ways are stable. When pole-mounted, the two-ways can sit level or be tilted downward 7.5° to aim at the audience if you are on a high stage. They also have integrated suspension points and optional hardware available for other mounting methods.
The ABS cabs are especially rugged and much stronger than, and acoustically superior to, the plastics used in most molded cabs. GuardRail technology prevents audible clipping and protects your investment. Speaker power handling is designed to handle the output of the integrated power modules. It all adds up to speakers that are built to hold up to heavy professional use. QSC backs them with a six-year warranty.
QSC’s advanced DS Technologies that were developed for their high-end gear have been built into these affordable and remarkable powered speakers. In the end, it’s sound quality that matters, and the K Series speakers make great sound easy.
Features & Specs
- 3 - 2-way models (with 8", 10", and 12" woofers) and a dual 12" subwoofer
- 2" or 2-1/2" voice-coil design for high power handling
- 1-3/4" diaphragm compression driver
- 1,000W Class D power modules in all models
- Directivity Matched Transition (DMT) and Intrinsic Correction DSP for accurate performance
- GuardRail technology discretely protects the systems from damaging overloads
- DEEP mode for enhanced low-frequency extension without a subwoofer
- EQ presets for flat or vocal enhancement
- 2 mixer channels (line level, one switchable to mic)
- XLR/1/4" combi TRS and RCA inputs
- Loop-thru connectors
- Coverage patterns optimized to match each LF driver
- Switchable front-mounted LED indicates Limit or Power On, or can be switched off
- Dual-angle, 35mm pole socket with tilting capability
- High-pass filter for use with subwoofers
- Threaded pole socket on KSUB (pole included)