KEF LSX II

The KEF LSX II is the most complete compact wireless speaker system KEF make — a fully active, fully connected stereo pair that replaces an entire hi-fi separates chain with two speakers and two power cables, without asking the listener to accept any compromise in acoustic performance or musical resolution. Built around the 11th generation Uni-Q® driver array, governed by KEF's Music Integrity Engine DSP platform, and powered by 200W of dedicated amplification across four channels per pair, the LSX II delivers a genuinely three-dimensional stereo presentation from a cabinet small enough to sit on a bookshelf, a desk, or a sideboard — and connects to virtually every source, digital and analogue, wired and wireless, that a modern listening life demands. At £1,250, it is a complete high-resolution music system in two cabinets.

11th Generation Uni-Q® Driver Array

The LSX II is built around a specially designed version of KEF's 11th generation Uni-Q® driver array — a 19 mm aluminium dome tweeter mounted at the acoustic centre of a 115 mm magnesium/aluminium alloy cone, in the coincident point-source arrangement that has defined KEF's loudspeaker philosophy for decades. This Single Apparent Source geometry ensures that treble and midrange radiate from precisely the same point in space — producing a soundstage of exceptional width and depth from a cabinet of remarkably modest dimensions, and a listening sweet spot far wider and more stable than a conventional two-way design of equivalent size can deliver. The two-way rear-ported bass reflex alignment extends frequency response to 49 Hz at −6 dB, with a maximum output of 102 dB — figures that place the LSX II's acoustic capability well beyond the reach of most wireless speakers at any price.

Each driver is powered by its own dedicated amplifier channel: 70W Class D for the bass/midrange driver and 30W Class D for the tweeter — 100W per speaker, 200W per pair. The amplifier channels are precisely matched to their drivers and governed by the Music Integrity Engine, which applies KEF's bespoke DSP algorithms — developed specifically to optimise the Uni-Q® driver's performance — to ensure that the relationship between amplification, crossover, and driver is as precisely calibrated as KEF's Reference-class designs.

Music Integrity Engine

The Music Integrity Engine is the signal processing architecture that coordinates all of the LSX II's acoustic and electronic systems. KEF's bespoke DSP algorithms manage crossover operation, driver linearisation, and the Room EQ system — which provides Normal and Expert modes, with compensation for wall, free-standing, and desktop placement — ensuring that the LSX II delivers consistent, optimised performance regardless of where it is placed in the room. Subwoofer crossover and level control are also managed through the Music Integrity Engine, allowing the LSX II to integrate cleanly with an active subwoofer for those who wish to extend bass performance further. The KEF KC62 Subwoofer pairs particularly well with the LSX II, and a dedicated RCA subwoofer output is provided on the primary speaker.

Wireless Connectivity and Streaming

The LSX II uses KEF's W2 wireless platform — supporting Wi-Fi (IEEE 802.11a/b/g/n/ac, dual-band 2.4 GHz and 5 GHz), Apple AirPlay 2, Google Chromecast, Bluetooth 4.2, and UPnP compatibility for music server and NAS integration. The system is Roon Ready. The KEF Connect app provides native access to Spotify Connect, Tidal Connect, Amazon Music, Qobuz, and Deezer — as well as Internet Radio — from a single interface on iOS or Android. For music files up to 24-bit/48kHz, the inter-speaker connection is entirely wireless, making the LSX II wireless in every respect at standard resolution. A linking cable is supplied for those streaming high-resolution files above 24-bit/48kHz via the network input, which supports PCM up to 24-bit/384kHz and DSD, as well as MQA decoding.

Wired Connectivity

The LSX II's connectivity goes considerably further than its compact dimensions might suggest. The primary speaker carries HDMI ARC for direct television connection, a USB Type-C input supporting audio up to 24-bit/192kHz, TOSLINK optical accepting up to 24-bit/96kHz, a 3.5mm analogue auxiliary input, and RJ45 Ethernet for a wired network connection. A dedicated RCA subwoofer output allows clean integration with an active subwoofer. This comprehensive wired connectivity makes the LSX II equally convincing as a desktop system connected to a laptop, a living room system connected to a television, or a dedicated music system driven from a network streamer or NAS.

Design

The LSX II was designed by Michael Young and is available in four standard finishes: Carbon Black and Cobalt Blue in fabric-wrapped Kvadrat textile, Mineral White in matte satin spray, and Lava Red in high-gloss spray. A fifth finish — the Soundwave by Terence Conran Edition — features a unique soundwave pattern woven into Kvadrat fabric. The curved cabinet form eliminates the parallel internal surfaces that cause standing waves in conventional rectangular enclosures, and the Kvadrat fabric wrap on the Carbon Black and Cobalt Blue models delivers a warmer, more domestic aesthetic that distinguishes the LSX II from the technical appearance of most active speakers.

Technical Specifications

Who Is It For?

The LSX II is for the listener who wants a genuine high-resolution music system — with the connectivity, streaming capability, and acoustic performance to justify that description — in the smallest possible physical footprint. It suits desks, bookshelves, and sideboards equally; it connects to televisions, laptops, turntables via an external phono stage, and virtually any network streaming source; and it delivers a stereo presentation that separates systems at this price point struggle to match. Those who want to extend bass performance can add the KEF KC62 Subwoofer — a combination that produces a full-range system of remarkable compactness. Those considering the step up to KEF's larger active loudspeaker should explore the KEF Blade Meta at the passive end of the range — both available to discuss at our Norwich showroom.

Buying from Martins Hi-Fi

Martins Hi-Fi has been in Norwich since 1968. Elizabeth Gould runs the business today, and we stock only brands we have heard properly and stand behind.

The LSX II is available to hear at our Norwich showroom — we can demonstrate it across a range of sources and streaming scenarios to show you exactly what it is capable of, and advise on whether it suits your room, your sources, and your listening habits. When you get in touch, you'll be speaking with Dave, Chris and Tim — experienced specialists who can advise on this product and your whole system.

Contact us at info@martinshifi.co.uk, call 01603 627010, or WhatsApp on 07554 687137. You can read more about how we work on our Why Martins Hi-Fi page. We are at 85–91 Ber Street, Norwich, NR1 3EY.