Loudspeakers

Measured on the Reference 7K's midrange axis – its most likely listening position – the loudspeaker's forward response [Graph 1] indicates both a boost to bass (below 500Hz) and treble (above 8kHz). It's also worth noting that the –1.5dB dip just prior to the 3kHz crossover increases to –3dB on the tweeter axis, so the speaker is certainly engineered to offer a smoother response on or above the midrange unit. That said, there's some fine structure visible at 3-6kHz that's also evident on the CSD waterfall [Graph 2], possibly indicative of modes from those 174mm 'ceramic tungsten' cones. Otherwise the Reference 7K's response uniformity is good to ±2.4dB and ±2.5dB, respectively, with a superb 0.6dB pair matching up to 14kHz, beyond which there's a more marked difference in treble response between our two samples. The magnetically attached grilles bring a further ~3dB disruption in presence band output [blue trace].

Sensitivity is only 0.8dB shy of Canton's rated 88.5dB at 87.7dB (1kHz) and 87.8dB (500Hz-8kHz) while the nominal impedance is a 'medium-tough' 4ohm. Intriguingly, the 7K includes a subsonic high-pass filter that causes a rising impedance/falling phase angle at very low bass frequencies, but it's most challenging through the mid-bass, with a 4.8ohm/–37° load at 88Hz. The lowest impedance modulus of 3.1ohm/335Hz should not trouble good amplifiers at this price point. And what about that bolstered bass output? The two woofers operate over a tight 58-170Hz bandwidth (–6dB), supplemented by a broad 25-109Hz from the downward-firing port, yielding a diffraction-corrected nearfield extension of 43Hz (–6dB re. 200Hz). PM