Полочная акустика — KEF LS50 Wireless II

The LS50 Wireless II is an active two-way stereo pair from KEF that places amplification, digital conversion and network streaming inside the cabinets. It is built on the 12th generation Uni-Q array with Metamaterial Absorption Technology (MAT) and is finished in Sand Shell, Moss Green, Mineral White or Carbon Black. Its US list price is USD 2,999.99 per pair. Power input is 100 to 240 V AC.

Key specs that matter

In every cabinet a vented 25 mm aluminium dome tweeter with MAT sits at the centre of a 130 mm aluminium cone for bass and midrange. Per speaker, the cone is driven by a 280 W Class D amplifier and the tweeter by a 100 W Class AB amplifier. KEF quotes a frequency response of 45 Hz to 28 kHz within plus or minus 3 dB and a frequency range of 40 Hz to 47 kHz at -6 dB, both measured at 85 dB and 1 m and dependent on EQ settings. Maximum output is 108 dB at 1 m. Each cabinet is 305 mm high, 200 mm wide and 311 mm deep, and the set weighs 20.1 kg.

Engineering and use context

For wired sources there are HDMI eARC, TOSLINK optical, digital coaxial, a 3.5 mm analogue auxiliary and RJ45 Ethernet, which also serves the link between the speakers, plus a USB Type A port for service. An RCA subwoofer output is fitted. Wireless support covers AirPlay 2, Google Cast, Roon Ready, UPnP and Bluetooth, with Spotify Connect, Tidal Connect, Qobuz, Amazon Music, Deezer and internet radio. The network input accepts up to 384 kHz and 24 bit, coaxial and HDMI up to 192 kHz and 24 bit, and optical up to 96 kHz and 24 bit. Over the network the speakers also decode MQA and DSD64 to DSD256, and every input handles MP3, M4A, AAC, FLAC, WAV, AIFF, ALAC, WMA, LPCM and Ogg Vorbis files. The two cabinets link either wirelessly, with every source resampled to 96 kHz and 24 bit PCM, or by cable, resampled to 192 kHz and 24 bit. DSP algorithms grouped as the Music Integrity Engine run inside. Control comes from the KEF Connect app, a touch panel on top and a supplied remote, and the system works with Elan, RTi, Crestron Home, Savant, Control4 and URC. Consumption is 200 W in operation and under 2 W in standby.

Pairing

Since the amplifiers sit inside the cabinets, the pair requires only a source such as a television through HDMI, a CD transport through a digital input or a phone or computer over the home network.

Alternatives

The KEF LSX II is a smaller active wireless bookshelf pair from the same brand.