KEF Q15 (1997–2000)

A compact bookshelf speaker system featuring KEF’s fourth-generation Uni-Q coaxial driver and a magnetically shielded bass reflex design.

Overview

The KEF Q15 is a two-way bookshelf speaker system introduced in 1997 and produced through 2000. It uses a single 16 cm coaxial driver per cabinet — KEF’s fourth-generation Uni-Q — combining a polypropylene cone woofer and a 1.9 cm soft dome tweeter in a point-source configuration. This design ensures coherent sound radiation and precise imaging, with the tweeter acoustically centered in the woofer cone. The system features a bass reflex enclosure with a geometrically shaped port and is magnetically shielded for safe use near CRT displays. The Q15 was designed for both stereo and bi-wiring or bi-amplification setups, with terminals to support either configuration.

Specifications

Frequency characteristic	50 Hz ~ 20 kHz ± 3 dB (within 30 degrees from central axis)
Impedance	6 Ω
Output sound pressure level	91 dB
Power handling	100 W
Crossover frequency	3.3 kHz
Enclosure volume	11.5 liters
External dimensions	Width 202 x Height 305 x Depth 245 mm
Weight	5.5 kg
Units Used For All Bands	16 cm Coaxial Type (16 cm cone + 1.9 cm dome)
Model Rating Method	2-way, 1-speaker, bass reflex system, bookshelf type, magnetic protection design

Design

The KEF Q15 features a fourth-generation Uni-Q coaxial driver, unique to KEF, with a 16 cm polypropylene cone woofer and a 1.9 cm soft dome tweeter. The tweeter uses neodymium iron boron magnet material — ten times stronger than ferrite — and ferrofluid for improved power handling. This allows fine adjustment of the tweeter’s position along the vibration axis, ensuring perfect phase alignment at the 3.3 kHz crossover point. The driver design improves tonal continuity from low to high frequencies through the use of a half-clear diaphragm and pure silk tweeter dome. The crossover network was designed using computer acoustic analysis, and the speaker has a mahogany finish with a geometric bass reflex port. A bi-wiring/bi-amplification terminal is provided.

Context

The KEF Q15 was introduced in 1997 and built on the success of the earlier Q10 model. It was positioned as a compact, high-performance bookshelf speaker system using the latest Uni-Q technology derived from KEF’s reference series.