Loudspeakers

While not quite the 8ohm specified by Totem, the Bison's minimum impedance modulus is still a very comfortable 5.4ohm/228Hz (warranting a 6ohm nominal rating) which, combined with equally 'easy' –39.7°/96.5Hz and +43.3°/1.09kHz phase angles, results in a minimum EPDR of 2.8ohm/52Hz. However, glitches in the impedance/phase curves at 420Hz, 770Hz and 920Hz presage a boost in the Bison's forward response of ~3dB at 800Hz-1.3kHz [see Graph 1] which, in turn, is reflected in resonance modes seen on the CSD waterfall plot [see Graph 2]. The latter are likely linked to the huge 76mm dustcap, or a cone/surround mistermination within the 133mm bass unit, but the overall response is otherwise very even, if slightly upturned towards the presence/treble. The grille produces a ~3dB drop in output at ~5kHz [blue trace, Graph 1]. Otherwise, pair matching is an exceptionally fine 0.4dB with response errors amounting to ±3.4dB and ±3.3dB, respectively, not including the 28kHz peak from the large (33mm) soft treble dome which pushes the Bison's HF response out to a respectable 34kHz (–6dB re. 10kHz).

Totem rates the Bison's sensitivity at 87dB but the 'bump' in response rather conveniently boosts the 1kHz figure to 87.8dB! However, figures of 84.8dB (500Hz-8kHz) and the IEC (perceptually)-wtd 83.0dB give a more realistic idea of perceived 'loudness'. Nevertheless, for a box of this size, impedance and sensitivity, distortion remains low at <0.7% (100Hz-10kHz re. 90dB SPL) while bass extension, aided by the 60Hz-600Hz (–6dB) woofer bandwidth and low 35Hz port tuning, reaches down to a respectable 41Hz (–6dB re. 200Hz) or 67Hz (–6dB re. 1kHz). PM