Fig.4 Revel Ultima Studio, anechoic response on-axis at 50", averaged across 30 degrees horizontal window and corrected for microphone response, with the complex sum of the nearfield midrange, woofer, and port responses plotted below 300Hz.
The Studio's lateral dispersion is shown in two forms: fig.5, which shows the actual responses, and fig.6, which shows just the differences between the tweeter's off- and on-axis responses, both plotted for off-axis angles up to ±90 degrees. It can be clearly seen from both graphs that the on-axis notch at 3.4kHz fills in to the speaker's sides, hence the ridge at this frequency in fig.6. I do wonder if this correlates with KR's occasional comment about brightness in his quite live room, but the Revel's dispersion is otherwise even and well-controlled. This always correlates with excellent soundstaging and image stability. Though the tweeter is surprisingly directional above 15kHz, I would not have thought this sufficient to explain KR's characterization of the Revel's highs as "soft." In the vertical plane (fig.7), the presence-region notch fills in off-axis, and the use of a high-order crossover means that the listening axis is not very critical.
Fig.5 Revel Ultima Studio, 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 Revel Ultima Studio, 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.
Fig.7 Revel Ultima Studio, vertical response family at 50", normalized to response on tweeter axis, from back to front: differences in response 15 degrees-5 degrees above reference axis, reference response, differences in response 5 degrees-10 degrees below axis.
