KEF Ci100QR In-Ceiling Speaker (Single)

The KEF Ci100QR sits within KEF’s Q Series of architectural speakers, designed for discreet in-ceiling installation. Part of KEF’s Soundlight range, the Ci100QR is purpose-built to blend with flush-mounted downlighting while delivering the performance expected of KEF’s Uni-Q driver technology.

Uni-Q Driver Array

At the heart of the Ci100QR is KEF’s Uni-Q driver array — a 100mm white polypropylene cone bass/mid unit with a 19mm aluminium dome tweeter mounted at its acoustic centre. This concentric arrangement means the entire frequency range radiates from a single point, producing wide, even dispersion across the listening area. In a ceiling application this is a decisive advantage: wherever you stand in the room, the tonal balance remains consistent rather than shifting with position.

Construction and Installation

The Ci100QR uses a double neodymium compound magnet system for its drive unit, keeping the motor assembly compact while maintaining the flux density needed for clean output. The speaker requires a cut-out diameter of just 118mm, and the mounting depth is 100mm for the driver alone or 145mm with the included detachable plastic rear can fitted. That rear enclosure provides a sealed volume of 0.7 litres, extending low-frequency performance down from 110Hz (open-backed) to 80Hz when installed.

Installation is straightforward: three spring-loaded clips hold the speaker flush against the ceiling surface as it is pushed into the cut-out, locking it securely in place without tools. The bezel and magnetic grille are both paintable, allowing the Ci100QR to match any ceiling finish.

Performance

With a frequency response of 80Hz–27kHz (±6dB, open-backed) and a crossover point at 3kHz, the Ci100QR covers the full range needed for distributed audio, background music, and home cinema surround channels. Sensitivity is rated at 88dB (2.83V/1m) with a nominal impedance of 4 Ohms. KEF recommends amplifier power between 10W and 50W, with a maximum power handling of 50W.