Revel Ultima Gem loudspeaker & Ultima Sub-15 subwoofer Measurements Page 5
In the time domain, the Gem's impulse response (fig.12) is typical of a design using a high-order crossover, but some reflections can be seen just over half a millisecond after the initial pulse, presumably from the side cheeks. The step response (fig.13) shows that the tweeter and the woofers are connected with the same positive polarity, but that the design is not time-coherent. Finally, the Gem's cumulative spectral-decay or waterfall plot (fig.14) looks clean enough, but whether or not residual resonant modes are present is obscured by the early reflections.—John Atkinson
Fig.12 Revel Ultima Gem, impulse response on tweeter axis at 50" (5ms time window, 30kHz bandwidth).
Fig.13 Revel Ultima Gem, step response on tweeter axis at 50" (5ms time window, 30kHz bandwidth).
Fig.14 Revel Ultima Gem, cumulative spectral-decay plot at 50" (0.15ms risetime).