This is typical Stereophile drivel. John Atkinson attempts to explain away mediocre results (slight lumpiness, lack of presence-region energy, etc.), saying, "This could be a measurement artifact."
A few years ago, John Dunlavy revealed Stereophile's measurement capabilities for being what they are: extremely flawed. And that frequency response graph doesn't look all that flat to me -- especially in the high frequency portion.
Judge for yourself. This is from Stereophile's measurements section in the review of the Revel Salon, which retailed for $14,400 in 1999:
"However, the high-order crossover means that the Salon cannot be time-coherent, as shown by its step response on the tweeter axis (fig.8). The tweeter output arrives first at the microphone, followed by the outputs of the midrange unit, then the upper woofer, then the three lower woofers. It is arguable whether time coherence is necessary or not. Certainly, LG's very positive reaction to the Revel's resolution of detail and its imaging accuracy was not negatively affected by the speaker's time-domain behavior.
". . . The Salon's waterfall plot (fig.9) was not as clean as I had expected. I suspect that some of the HF hash present in the floor of this graph is due to early reflections of the tweeter's output from the tops of the speaker's side cheeks. There is a hint of delayed energy just below the on-axis notch in the presence region, but this is probably too subtle to introduce any coloration.
". . . Another finely engineered loudspeaker design from Kevin Voecks and his team. John Atkinson"
Indeed. Are we talking about the same speaker? The main problem, though, is that these speakers just don't sound that great compared to the competition at this price and even one-third the price.