Sonus faber Maxima Amator Loudspeaker Lab Report

Lab Report

Compared with the Electra Amator III [HFN Jul '19], the Maxima's more complex third-order crossover (down from 2.5kHz to 2.1kHz) and increased cabinet volume bring improved bass extension and ease-of-drive for a slightly reduced 87dB (200Hz20kHz) or 85.5dB (500Hz-8kHz) sensitivity. The Maxima is still a nominal 4ohm load, but its minima are higher at 4.0ohm/16.5kHz, 4.05ohm/142Hz and 4.5ohm/38Hz, while phase angles are 53°/55Hz and –62°/70Hz. So it's only moderately challenging!

These impedance and phase spectra also reveal a mild inflection at the ~2kHz crossover, seen as a reinforcement in the forward response [black/red traces, Graph 1] and as a dominant mode in the CSD waterfall [Graph 2] – possibly a mistermination between the pulp bass/mid cone and its rubber surround. THD also rises slightly from the low ~0.4% achieved through bass and treble to 0.5-0.6% at this same 1-5kHz (re. 90dB SPL at 1m). Otherwise, the Amator Maxima's response trend is flat to within ±2.0dB prior to a +5dB lift above 5kHz (measured on Sonus faber's reference axis above the treble dome). Toeing the speakers a little off-axis will likely bring the mid and treble into balance at ~3m listening distances. Pair matching is superb at 1.0dB (200Hz-20kHz) while the small magnetically-attached grille has little adverse impact [blue trace, Graph 1].

The pulp bass/mid driver has a usefully wide 52-440Hz/–6dB bandwidth while diffraction-corrected nearfield measurement shows this combines with the higher-Q 35Hz output of the rear port (albeit with spurious modes at 240Hz and 780Hz) to deliver a generous 37Hz (–6dB re. 200Hz) bass extension. PM


Response inc. nearfield summed driver/port [green], freefield corrected to 1m at 2.83V [yellow], ultrasonic [pink]. Left, black; right, red; w. grille, blue


Resonances are quickly suppressed, albeit with a mode remaining near the 2.1kHz crossover [Graph 1]

Sensitivity (SPL/1m/2.83V – 1kHz/Mean/IEC) 85.1dB / 85.5dB / 84.5dB
Impedance modulus: minimum & maximum (20Hz–20kHz) 4.0ohm @ 16.5kHz, 48ohm @ 63Hz
Impedance phase: minimum & maximum (20Hz–20kHz) –62° @ 70Hz, +53° @ 55Hz
Pair matching/Resp. error (200Hz–20kHz) 1.0dB/ ±4.9dB/±5.0dB
LF/HF extension (–6dB ref 200Hz/10kHz) 37Hz / 40.6kHz/38.9kHz
THD 100Hz/1kHz/10kHz (for 90dB SPL/1m) 0.4% / 0.55% / 0.35%
Dimensions (HWD) / Weight (each) 1120x300x350mm / 38kg
Price £14,500

Sonus faber SpA (Fine Sounds Group)
Supplied by: Fine Sounds UK
01592 744710