Loudspeakers

We weren't quite able to confirm Focal's claimed sensitivity for the Kanta No3 of 91dB, our pink noise and 'music' figures of 89.9dB and 89.5dB SPL respectively for 2.83V at 1m suggesting that 1dB lower (or 90dB) is a more realistic figure. We've often seen Focal resort to low impedance to achieve high sensitivity from its speakers and it's no different here. While quoting an 8ohm nominal impedance Focal admits to a minimum of 3ohm, suggesting rather a 4ohm nominal rating. We measured a slightly lower minimum of 2.9ohm and large impedance phase angles at low frequencies which together reduce the EPDR (equivalent peak dissipation resistance) to a punishing low of 1.2ohm at 82Hz. So the Kanta No3 is not a speaker to partner with amplifiers at all reticent about delivering high current.

Forward frequency responses for the pair, measured at 1m on the tweeter axis [see Graph 1, below] show very fair errors of ±3.9dB and ±3.6dB, respectively, despite an obvious 'BBC dip' through the presence band and rising output close to 20kHz. These response errors would have been lower still but for the narrowband suckout at 7kHz. (Ignore the dip below 300Hz which is an artefact of the measurement's time windowing.) Pair matching over the same 200Hz-20kHz frequency range is outstandingly good at ±0.6dB. Diffraction-corrected summed nearfield measurements showed the bass response to extend down to 42Hz (–6dB re. 200Hz). Focal speakers have commonly not produced such clean cumulative spectral decay waterfalls as some competitors, and that too is the case here [see Graph 2]. Ridges in the plot – repeated in both speakers of the pair – show a series of resonances above 5kHz. KH