Loudspeakers

Measured again on the tweeter axis – the centre of the DPC array – how does this LE version compare with the standard S7t [HFN Apr ’22]? The forward response [Graph 1] remains very uniform with errors of just ±1.5dB and ±1.6dB (200Hz-10kHz) increasing to ±2.9dB and ±2.6dB, respectively, between 10-20kHz, just as pair matching is a tight 0.75dB. However, the LE adds a broad +1.5dB reinforcement from 2.5kHz-7kHz, ostensibly enhancing its presence/treble, while the magnetically attached grilles introduce a slightly more exaggerated ±0.8dB variation through this same region [blue trace]. Again, there’s no avoiding the +5.9dB treble dome resonance just outside the audioband at 23.7kHz, and the –5.1dB notch at 20.5kHz that precedes it [pink shaded area, Graph 1, and see also CSD waterfall, Graph 2]. As expected, the array’s off-axis uniformity is excellent [grey trace].

As in the standard S7t model, sensitivity is only slightly under Perlisten’s claimed 92dB (91.2dB/1kHz/2.83V and 91.5dB from 500Hz-8kHz), this aiding low distortion at high levels (<0.2% re. 90dB SPL/1m/100Hz-10kHz). Nearfield analysis shows the mid/bass Textreme cones have an extended 51Hz-1.15kHz bandwidth (–6dB), while all four cones, plus the limited dual-port/slot output at 22Hz, maintain the S7t’s modest, diffraction-corrected 49Hz bass extension (–6dB re. 200Hz). While both bass extension and sensitivity are unchanged, the LE model does present a tougher amplifier load from 20Hz-1kHz. The minimum impedance is now 2.68ohm/126Hz which, with swings in phase angle of –39°/79Hz and +51°/975Hz, combine to produce a minimum EPDR of 1.38ohm/94Hz, and a sub-2ohm stretch from 200Hz-900Hz. PM