KEF R3 Meta Loudspeaker Lab Report
No 'fantasy specifications' here as the most compact of KEF's R Meta series delivers exactly what it says on the tin (ok, website). The 3.2ohm minimum/4ohm nominal impedance rating is met in practice with 3.17ohm at 142Hz although the load is <4ohm from 112Hz-835Hz and the EPDR a moderate 1.65ohm/875Hz. Impedance is 'squeezed' through the bass with a maximum 8.2ohm/35Hz, a (port) dip of 3.5ohm/40Hz and EPDR of 1.78ohm/39Hz, the 'real' impedance peak occurring at a high 2.75kHz. The latter may be sufficient to provide a lift in upper mid response if the R3 Meta is driven with a tube- or other amp with a moderate/high source impedance. Under ideal conditions the R3 Meta offers a very even, fractionally downtilted response [Graph 1] with mere ±1.6dB and ±1.5dB errors (200Hz-20kHz) and superb 0.3dB pair matching, the MAT disc quelling any treble resonances post-2.3kHz crossover [CSD waterfall, Graph 2].
However, as we've seen with Uni-Q in the past, the MAT absorber does not attenuate the +10dB breakup of the 25mm vented alloy dome, here at 39.5kHz [pink shaded area, Graph 1]. Neither does it have any influence over the cancellation notches at 7.3kHz and 15.6kHz on the forward output of the Uni-Q driver through the perforated grille [blue trace, Graph 1]. Otherwise, THD from the 125mm alloy mid cone is 'state-of-the-art' low at ~0.05% (re. 1m/90dB SPL) just as KEF's rated 87dB sensitivity is also spot-on at 1kHz/1m, and only slightly over-optimistic at 86.8dB when averaged across 500Hz-8kHz. Bass extension is good for the limited cabinet volume, its ported 165mm alloy woofer reaching down to 40Hz (–6dB re. 200Hz). PM
Sensitivity (SPL/1m/2.83V – 1kHz/Mean/IEC) | 87.0dB / 86.8dB / 84.9dB |
Impedance modulus: minimum & maximum (20Hz–20kHz) | 3.17ohm @ 142Hz, 14.0ohm @ 2.75kHz |
Impedance phase: minimum & maximum (20Hz–20kHz) | –33° @ 38Hz, +45° @ 1.46kHz |
Pair matching/Resp. error (200Hz–20kHz) | 0.3dB/ ±1.6dB/±1.5dB |
LF/HF extension (–6dB ref 200Hz/10kHz) | 40Hz / 51.0kHz/50.3kHz |
THD 100Hz/1kHz/10kHz (for 90dB SPL/1m) | 0.15% / 0.05% / 0.3% |
Dimensions (HWD) / Weight (each) | 422x200x336mm / 12.4kg |
Price | £1899 (£649 stands) |