Loudspeakers

is responsible for a blip (2.9dB) in pair matching and is also seen on the CSD waterfall [Graph 2] although the resonance is at a low level. Otherwise the response is broadly 'flat' prior to a peak in output of the silk 'Damped Apex Dome' at 18kHz that, in turn, pushes up the response errors to ±4.8dB and ±5.0dB, respectively (re. 200Hz-20kHz). Sonus faber claims a 40kHz extension for this latest version of the tweeter and, indeed, it reaches out to a fine 49kHz [-6dB re. 10kHz, pink shaded area Graph 1]. There's an obvious roll off in HF output off-axis [grey trace, Graph 1], but the subjective balance may be preferable. Incidentally, the mid/treble grille causes a notch at 6-7kHz - you may want to remove it for critical listening [blue trace, Graph 1].

The lift in midband output boosts sensitivity to 90.1dB/1kHz (better than the rated 89dB) but the figure is a little lower at 88.6dB when averaged across 500Hz-8kHz. The down-firing port, meanwhile, helps conceal a quarterwave mode at 140Hz and others at 500Hz and 900Hz (also seen on the phase/ impedance plots) but the 36Hz tuning does assist in the final extension to 38Hz (-6dB re. 200Hz) of what is a fairly 'peaky' bass alignment [green shaded area, Graph 1]. Good sensitivity and a punchy bass come at the expense of a fairly tough load where the 2.78ohm/96Hz minimum and +49o/-66o swings in phase angle from 20Hz-100Hz all contribute to this speaker's 1.1ohm/82Hz EPDR. Bass freaks - this will test your amplifier. PM

Sensitivity (SPL/1m/2.83V – 1kHz/Mean/IEC)	90.1dB / 88.6dB / 87.1dB
Impedance modulus: minimum & maximum (20Hz–20kHz)	2.78ohm @ 96Hz 32.0ohm @ 27Hz
Impedance phase: minimum & maximum (20Hz–20kHz)	–66.1o @ 69Hz +49.3o @ 23Hz
Pair matching/Resp. error (200Hz–20kHz)	2.9dB/ ±4.35dB/±5.0dB
LF/HF extension (–6dB ref 200Hz/10kHz)	38Hz / 48.9kHz/44.8kHz
THD 100Hz/1kHz/10kHz (for 90dB SPL/1m)	0.6% / 0.3% / 0.3%
Dimensions (HWD) / Weight	1081x308x415mm/33.4kg
Price	£5500