Naim NBL loudspeaker Measurements part 2
Fig.4 Naim NBL, anechoic response on tweeter axis at 50", averaged across 30 degrees horizontal window and corrected for microphone response, with the complex sum of the nearfield woofer and midrange responses plotted below 300Hz.
Figs.5 and 6 show the NBL's lateral dispersion, without (fig.5) and with (fig.6) the tweeter-axis response subtracted. While the upper-midrange energy peak persists off-axis, which will exaggerate its audibility, the speaker's dispersion is relatively well-controlled. What appear to be off-axis ridges in fig.6 are primarily due to on-axis suckouts filling-in to the speaker's sides.
Fig.5 Naim NBL, lateral response family at 50", from back to front: responses 90 degrees-5 degrees off-axis, reference response on tweeter axis, responses 5 degrees-90 degrees off-axis.
Fig.6 Naim NBL, lateral response family at 50", normalized to response on tweeter axis, from back to front: differences in response 90 degrees-5 degrees off-axis, reference response, differences in response 5 degrees-90 degrees off-axis.