Loudspeakers

Taking the midrange PM driver out of the FR10 floorstander to collapse the three-way into a compact two-way - the FR5 tested here - means the 165mm 'bass' unit is now obliged to work right up to the 1.75kHz tweeter crossover (and the 64mm PM tweeter down to meet it). This bass/mid driver is the same size as those used in the FR10 but fashioned from a lower mass 'woven polypropylene' and loaded by just one of the FR10's rear-firing 'racetrack' ABRs. The latter is tuned to 35Hz, supplementing the peak 110Hz output of the woofer to deliver a diffraction-corrected bass extension of 40Hz (-6dB re. 200Hz) before a steep, deep bass roll-off [green shaded area, Graph 1].

The forward response shows a dished mid/presence output after a 400Hz-1kHz 'boost' that not only lifts the sensitivity from PS Audio's rated 83.5dB to 84dB/1kHz but is also linked to mild driver modes on the CSD waterfall [see Graph 2] and also a 1.4dB variation in pair matching. Sensitivity is a much reduced 81.7dB from 500Hz-8kHz but the response picks up again as the PM tweeter takes over, rising to +3dB/20kHz (re. 1kHz). On the upside, the mid/treble response errors of ±3.9dB and ±4.4dB, respectively, are ~0.5dB tighter than those observed with the FR10 and are reduced still further to ±2.7dB and ±3.2dB if the FR5s are toed in by 15o [grey trace, Graph 1]. Low sensitivity means THD is higher than average at 2-0.5% (100Hz-10kHz, re. 90dB SPL/1m) but there's a payoff in an 'easy' impedance. The 5.6ohm rated minimum is met at 5.8ohm/138Hz and, despite -59o/+53o swings in phase angle through the bass pushing the EPDR down to 2.5ohm/105Hz, this is not especially taxing. PM

Above: Response inc. nearfield summed driver/ABR [green], freefield corrected to 1m at 2.83V [yellow], ultrasonic [pink]. L, blk; R, red; ±15o, grey; grille, blue

Above: Mild modes associated with the polypropylene mid, and notch at 10kHz, but tweeter is ‘clean’