Loudspeakers

While the R 8 is a fairly sensitive tower – Audiovector rates it as 92.5dB but it appears closer to 87dB/1kHz and 89dB (500Hz-8kHz) – it is also a very tough load (the 8ohm nominal rating is wide of the mark). The good sensitivity partially mitigates the low impedance because less current will be drawn from the amplifier for a given output level. However, with a sub-7.5ohm load (20Hz-20kHz), a minima of 2.5ohm/80Hz and low EPDRs of 1.3ohm/37Hz, 1.4ohm/73Hz and sub-2ohm from 270Hz-1.3kHz, the R 8 will favour big amps with a low source impedance.

Measured on the most likely listening axis (in line with the top mid/woofer) the R 8 shows a distinctly upper-mid-forward response [Graph 1] with a peak centred around 4.6kHz that's some +6dB higher than the mean midband output and also largely responsible for the ±4.3dB and ±4.7dB response errors. Pair matching is an impressively tight 0.6dB up until the AMT tweeter gets into its stride >6kHz where it widens to 1.6dB, although the treble extension remains a reliably high ~47kHz (–6dB re. 10kHz) for both speakers. The upper-mid peak is also associated with a resonance on the CSD waterfall [Graph 2] along with a possible cone/surround mistermination (and dip in response) at 1kHz from the top mid/woofer. Distortion at 1kHz, and through the midrange, is spectacularly low, however, at ~0.05% (re. 90dB SPL). The acute 73Hz tuning of the vented, isobaric bass section dominates the R 8's punchy low bass [green shaded area, Graph1] supplementing the main drivers that reach down to a broader peak at ~60Hz (the upper unit extends up to 4kHz). Corrected bass extension is 37Hz (–6dB re. 200Hz). PM