B&W Matrix 801 Series 2 loudspeaker Measurements
In the vertical plane (fig.7), the Matrix 801's use of high-order crossover filters makes it fairly insensitive to listener position, the response hardly changing over quite a wide ±10 degrees window centered on the tweeter axis. Only at 15 degrees above the tweeter axis does a suckout start to develop at around 3kHz, in the upper crossover region.
Fig.7 B&W Matrix 801, vertical response family at 50", from back to front: differences in response 15 degrees-5 degrees above tweeter axis, reference response, difference in response 5 degrees below tweeter axis.
In the time domain, the impulse response (fig.8) is absolutely typical of a design that uses a high-order crossover. The glitch just before the 8ms line in this graph is due to a reflection from the floor—I couldn't lift the 801 off the ground for this measurement. The step response (fig.9) indicates that the tweeter, midrange, and woofer outputs are all in the same, positive-going polarity, but that the speaker is far from time-coherent, despite its stepped-back baffle arrangement. However, the fact that each drive-unit's step hands over neatly to that of the next lower in frequency implies good integration in the frequency domain, as shown in fig.4.
Fig.8 B&W Matrix 801, impulse response on tweeter axis at 50" (5ms time window, 30kHz bandwidth).
Fig.9 B&W Matrix 801, step response on tweeter axis at 50" (5ms time window, 30kHz bandwidth).
Finally, the B&W Matrix 801's cumulative spectral-decay plot on the tweeter axis is superbly clean (fig.10). Overall, though its on-axis response and lateral dispersion suggest a balance that will be a little too much on the "ruthlessly revealing side"—as, of course, is necessary for a monitor design—this is excellent measured performance, supporting Lewis Lipnick's longstanding enthusiasm for the speaker.
Fig.10 B&W Matrix 801, cumulative spectral-decay plot at 50" (0.15ms risetime).
Despite its vintage, the 801 is a grain-free, smooth-sounding, basically neutrally balanced transducer that remains competitive 15 years after its introduction. It is no wonder that, even at its $5000/pair price—equivalent to around $13,000 in today's money—the B&W Matrix 801 sold extremely well throughout the late 1980s and early '90s. It is a worthy ancestor to B&W's later no-holds-barred Nautilus 801.—John Atkinson