Scansonic MB6 B Loudspeaker Lab Report
Scansonic continues to specify a high sensitivity for its reworked 'B' series but the depressed midband and shelved-up presence/treble of the MB6 B suggests a standard 1kHz figure of just 84.1dB (re. 2.83V/1m) improving to 84.9dB (500Hz-8kHz) and 86.3dB (200Hz-20kHz). As we saw with the MB5 B, narrowband variations in the output of the planar treble driver above the 2.6kHz crossover contribute to response errors of ±4.9dB with a hefty pair-matching error of 3.6dB. On the other hand, HF distortion is lower in this model at 0.6%/10kHz/90dB SPL and break-up behaviour better controlled [see Graph 2, below].
Working with a 'line array' of small woofers brings both benefits and challenges – the low frequency alignment here is decidedly 'peaky' with all four reflex-loaded 115mm bass units tuned to 79Hz and a steep roll-off thereafter [green shaded area, Graph 1]. While the diffraction-corrected bass extension of 54Hz (–6dB re. 200Hz) may seem slightly parsimonious, in practice we found the MB6 B certainly benefited from some near rear-wall reinforcement, these slim floorstanders delivering their smoothest, deepest subjective bass in this location. So the MB6 Bs are certainly room-friendly, but the amplifier loading – particularly below 150Hz – is a little tougher than Scansonic's '>4ohm' specification might suggest. Even though swings in phase angle are limited to +47°/–29° through this region, the impedance minima of 3.1ohm/89Hz and 2.98ohm/25Hz are best handled by heavyweight solid-state amps, particularly when the reduced sensitivity is also taken into account. Then again, a £9000 flagship is unlikely to be partnered with anything less! PM
Sensitivity (SPL/1m/2.83V – 1kHz/Mean/IEC) | 84.1dB / 84.9dB / 86.3dB |
Impedance modulus: minimum & maximum (20Hz–20kHz) | 3.0ohm @ 25Hz, 13ohm @ 69Hz |
Impedance phase: minimum & maximum (20Hz–20kHz) | –29° @ 78Hz and 2.9kHz, +47° @ 56Hz |
Pair matching/Resp. error (200Hz–20kHz) | 3.6dB/ ±4.9dB/±4.9dB |
LF/HF extension (–6dB ref 200Hz/10kHz) | 55Hz / 47.7kHz/44.7kHz |
THD 100Hz/1kHz/10kHz (for 90dB SPL/1m) | 0.35% / 0.28% / 0.56% |
Dimensions (HWD) / Weight (each) | 1410x178x410mm / 37kg |
Price | £8999 |