Loudspeakers

Modern floorstanders as large as the AF-61 typically record sensitivities of 89dB or 90dB so it’s a surprise to find that ELAC specifies 87dB, and that our measured pink noise figure is just under 86dB. Classically, you’d expect this to be accounted for by the AF-61 having greater bass extension than competitors and/or higher impedance – and that’s the case. Although our diffraction-corrected nearfield measurement recorded a bass roll-off of 46Hz (–6dB re. 200Hz) – not a stellar bass extension for a large speaker – it does beat the 55Hz or so we commonly measure from high-sensitivity floorstanders. And the AF-61 is also rather more amplifier-friendly. Our measured impedance minimum of 4.7ohm is relatively high these days and sits well with the 6ohm nominal specification. However, its impedance phase angles are high enough to drop the EDPR (equivalent peak dissipation resistance) to a low of 2.0ohm at 74Hz, which is less than you’d expect of that minimum modulus but usefully 0.3ohm higher than we typically record.

Forward frequency responses, measured at 1m on the axis of the coaxial driver [Graph 1] reveal a generally flat trend but there are wiggles above 4kHz associated with the coaxial driver which increase the response errors to ±3.4dB and ±3.9dB respectively (300Hz-20kHz). Pair matching is disappointing at ±2.0dB, the largest disparities again occurring in the treble. You can ignore the roll-off below 300Hz for, in fact, the response is well maintained down to 65Hz, below which it falls away with a fourth-order slope. The CSD waterfall [Graph 2] suggests the mild 2kHz response dip is associated with a resonance, with only a cluster of low-level modes visible above that. KH

Sensitivity (SPL/1m/2.83V – Mean/IEC/Music): 85.8dB/85.9dB/85.9dB
Impedance modulus: minimum & maximum (20Hz–20kHz): 4.7ohm @ 95Hz / 15.4ohm @ 1.9kHz
Impedance phase: minimum & maximum (20Hz–20kHz): –56° @ 64Hz / 43° @ 20kHz
Pair matching/Resp. error (300Hz–20kHz): ±2.0dB / ±3.4dB / ±3.9dB
LF/HF extension (–6dB ref 200Hz/10kHz): 46Hz / 24.5kHz/25.6kHz
THD 100Hz/1kHz/10kHz (for 90dB SPL/1m): 0.2% / 0.2% / 0.8%
Dimensions (HWD) / Weight (each): 1329x244x398mm / 46kg
Price: £5200