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A Compact Subwoofer That Sounds Great: KEF KC 92

If you want powerful bass in your home theater or two-channel listening room, but don’t have the space for a large subwoofer, there’s a new contender in the small, plays loud category. KEF has recently retired their very successful, compact KF92 and introduced the new KC92 subwoofer, and we love it. 

With subs, in general, the bigger the cabinet, the more bass output. But many customers won’t buy a big sub, preferring a small, high output, musical subwoofer like this. The KC92 can hit 110dB sound pressure levels (an upgrade of 5 dB from the KF 92) from the same size cabinet. That’s an engineering achievement for sure. The result is a LOT of bass output from such a compact cabinet.  

With KC92, kick drums really sound like kick drums, and it stays clean. KEF specifies this sub as providing you with useable output well below 20 cycles, down to 11 Hz. We don’t know of many other subwoofers with such compact dimensions - roughly 13 x 13 x 14 inches - that can reproduce such deep bass frequencies loudly and cleanly.

KEF borrowed the idea from their amazing flagship Blade II speaker to use twin drivers, placed back-to-back. This is called a force-canceling design. The 9” drivers move in sync with each other, canceling cabinet resonances so that you hear clear, detailed musical notes from the driver output, not rattling cabinet vibrations.

The drivers are not paper or aluminum cones, but rather a hybrid driver: a thin aluminum cone is bonded to a thin paper cone. The combination is a fast-responding driver that doesn’t break up under heavy pounding. The P-Flex surround (suspension) has an origami-like series of folds, strong yet light. That allows fast movement without flexing. Inside you get a vented voice coil design to minimize heat buildup. This sophisticated combo driver is key to clean output.  

Twin 500-watt amplifiers, one for each driver, keep the twin drivers under control. For loud, deep bass, you need high power for control, but it is important to avoid excessive heat buildup. KEF’s class D amplifiers run cool. The cabinet is sealed, not ported, and bass notes stay musical.  

KEF’s proprietary Music Integrity Engine (MIE) is a custom set of algorithms that digitally controls driver motion, monitoring the amplifier and driver so that the entire system interacts together. Their Intelligent Bass Extension system is part of those algorithms, dynamically comparing the input signal vs the output signal, making continuous small adjustments so that you get the most clean output possible, without noticeable distortion.  

The rear panel offers excellent connectivity, too. You can even customize your sound with a five-way switch that allows you to choose the best setting, optimizing the subwoofer’s performance based on where in the room you have placed it. The options are: close to a wall; in a corner; close to a cabinet; in free space, away from the walls; or in apartment mode. KEF Smart-connect will even figure out whether you are using the sub in mono or stereo configuration, and adjust output accordingly. 

Do you need wireless placement? Apartment dwellers love this feature. KEF’s KW-1 Wireless system is available if you cannot run wires where you want to place your sub. KC92 is also future-ready. It features a USB-C input, for convenient firmware updates later. You can easily bring KC92 up to the latest specs from the comfort of your own home.

Getting great bass from a subwoofer isn’t easy. Getting great bass from a compact sub that complements the look of your home is even harder. KEF KC92 is a sub to consider if you want impressive bass from a compact, classy-looking cabinet.