KEF Reference 5 Meta Loudspeaker Lab Report

Lab Report

In practice this 'Meta' version of the original Reference 5 [HFN Oct '14] has evolved from tip-to-toe. KEF's specs reflect this too – bass extension is unchanged, but sensitivity is down from 89.5dB to 88dB and the Uni-Q crossover adjusted from 2.8kHz to 2.1kHz, etc, in this latest model. Once again, the typical listening axis will lie a little above the (now) 12th-gen Uni-Q mid/treble driver where its 39.6kHz dome resonance is reduced in severity from ~17dB to ~6dB above the mean midband level [blue trace, Graph 1]. Otherwise, the effect of the 'labyrinthine' Meta disc in quelling mid-treble resonances above the 2.1kHz crossover is evident in the CSD waterfall [Graph 2, below] just as conventional harmonic distortions are also a creditably low 0.25% (re. 90dB SPL).

The forward response shows the same slightly downtilted trend we saw in the Reference 5 but with tighter errors of just ±2.0dB and ±2.1dB, respectively, caused as much by the general uplift in low mid/bass below 600Hz. Pair matching is a superb 0.6dB. The 88.4dB/1kHz axial sensitivity (or 89.2dB from 500Hz-8kHz) is reduced by about 1.5dB if you listen ~20cm above the Uni-Q axis, but these figures are still within the compass of KEF's latest 88dB specification. Otherwise, this good sensitivity and 33Hz (re. 200Hz) bass extension has, in part, been bought at the expense of a slightly tougher amplifier load than we encountered with the original Reference 5 – KEF's 4ohm (3.2ohm min) impedance rating being closer to 2.7ohm/73Hz and sub-4ohm from 29-280Hz in the '5 Meta. The minimum EPDR is 1.3ohm/30Hz (and 1.5ohm/895Hz). PM


Response inc. nearfield summed driver/port [green], freefield corrected to 1m at 2.83V [yellow], ultrasonic [pink]. Left, black; right, red; off-axis, blue

KEF Reference 5 Meta_Waterfall_R_46in_40dB

Minor breakup modes associated with the alloy bass drivers but Meta scrubs the treble clean

Sensitivity (SPL/1m/2.83V – 1kHz/Mean/IEC) 88.4dB / 89.2dB / 87.6dB
Impedance modulus: minimum & maximum (20Hz–20kHz) 2.7ohm @ 73Hz, 15ohm @ 2.2kHz
Impedance phase: minimum & maximum (20Hz–20kHz) –42° @ 28Hz, +48° @ 1.28kHz
Pair matching/Resp. error (200Hz–20kHz) 0.6dB/ ±2.0dB/±2.1dB
LF/HF extension (–6dB ref 200Hz/10kHz) 33Hz / 53.9kHz/53.6kHz
THD 100Hz/1kHz/10kHz (for 90dB SPL/1m) 0.35% / 0.25% / 0.45%
Dimensions (HWD) / Weight (each) 1350x205x462mm/60kg
Price £17,500

GP Acoustics (UK) Ltd
Maidstone, Kent
Supplied by: GP Acoustics (UK) Ltd
01622 672 261