KEF Kube 12 MIE

The Kube 12 MIE is the second largest model in KEF's four-strong Kube MIE subwoofer range, sitting above the Kube 8 MIE and Kube 10 MIE and below the flagship Kube 15 MIE. KEF positions it for movies, music, TV and gaming in larger rooms and dedicated home theatres. A 300mm (12in) front-firing driver is paired with a 300W RMS Class-D amplifier in a sealed cabinet, and the whole system is managed by KEF's Music Integrity Engine.

Music Integrity Engine

Music Integrity Engine (MIE) is KEF's in-house suite of DSP algorithms, tailored to each model in the range so that driver, amplifier and cabinet work together rather than in isolation. Within it, iBX Intelligent Bass Extension analyses the incoming signal and makes constant small adjustments, which extends the usable depth of the driver and keeps the subwoofer dynamic at any listening level. KEF says that having learned from the development of the LS60 Wireless and KC62, it was able to improve accuracy further with MIE in the Kube, especially at high output levels, while this newer version of iBX lowers distortion still further.

Driver and Amplification

The 300mm front-firing drive unit is a long-throw design with a large cone area, which produces higher output at lower frequencies and delivers bass as direct force into the room. Amplification is a 300W RMS Class-D stage, designed specifically around this driver and the cabinet's acoustic volume, and it runs efficiently and cool. Frequency response is quoted at 22Hz to 140Hz (+/-3dB) with a maximum output of 114dB.

Sealed Cabinet and Room EQ

Kube uses a sealed enclosure rather than a ported one, which KEF specifies for greater accuracy and which also allows the subwoofer to be installed inside a cabinet. Because boundaries reinforce bass, the Kube 12 MIE carries three room placement EQ settings that compensate for the position it is used in, whether that is fitted into a cabinet, placed against a wall or tucked into a corner. The cabinet itself is finished in black with a minimal, contemporary profile.

Connections and Control

Connectivity covers RCA phono sockets, speaker level inputs and an expansion port for the optional KW1 wireless subwoofer adapter, so the Kube 12 MIE can be driven from an AV receiver, a preamplifier or directly from an amplifier's speaker terminals. KEF SmartConnect detects automatically whether one or two RCA cables are connected and adjusts gain to suit, so no Y-adapter is needed. Manual controls comprise a variable low-pass filter covering 40Hz to 140Hz at 24dB per octave plus an LFE setting, a phase control switchable between 0 and 180 degrees, and a volume control.

Power Modes

Three power modes are provided on a rear-panel selector. Auto Wake up powers the subwoofer on when it detects an audio signal and shuts it down after 20 minutes of inactivity; Always On keeps it permanently awake until the main power switch is used; and the 12V setting slaves the Kube to the 12V trigger output of a compatible amplifier or receiver.