112 MACWORLD JUNE 2019
PLAYLIST REVIEW: KEF LSX WIRELESS MUSIC SYSTEMThe KEF Uni-Q driver consists of a 0.75-
inch aluminum-dome tweeter located at the
center of a 4.5-inch magnesium/aluminum
alloy-cone midrange/woofer.
the KEF Control app: 49-, 52-, or 55Hz. By
contrast, the frequency response (±3 dB) is
specified up to 28kHz and down to 54-,
59-, or 69Hz, depending on the Bass
Extension setting. The low end is
enhanced by a port on the back of the
speaker as well as KEF’s Music Integrity
Engine digital signal processing. The
maximum output is spec’d at 102dB SPL.
As a wireless speaker, the LSX accepts
audio via Bluetooth 4.2 (with support for
the aptX codec), and it will remember up
to eight Bluetooth devices. It will also
support Apple AirPlay 2 in a soon-to-be-
released firmware update. In addition, it
can stream music from online providers
Tidal and Spotify as well as local NAS
drives or computers via DLNA over your
home’s Wi-Fi network (2.4- or 5GHz,
802.11a/b/g/n).
The LSX supports digital-audio streams
with resolutions up to 192kHz/24-bit.
Ethernet connections, however, max out at
96/24, and wireless connections are
limited to 48/24, so anything higher is
downsampled as needed.
This speaker is sold in pairs; one is
called the Master and the other is called
the Slave. The Master provides all the
connections on its back panel, including a
TOSlink optical digital-audio input and a
3.5mm 2-channel analog-audio input as
well as a hardwired ethernet connector for
greater bandwidth on your network. OtherA gently convex front baffle helps
minimize diffraction of sounds from the
driver. Speaking of which, the driver is a
KEF-developed Uni-Q coaxial design. A
0.75-inch aluminum-dome tweeter is
located at the center of a 4.5-inch
magnesium/aluminum alloy-cone
midrange/woofer. This configuration is
intended to make sounds from both
transducers radiate from the same point
and improve stereo imaging.
The Uni-Q driver is powered by
amplifiers providing 70 watts for the
midrange/woofer and 30W for the tweeter.
KEF specifies a frequency range (-6 dB) up
to 47kHz; the low end of that range
depends on the Bass Extension setting in