One thing that I'm a bit puzzled about is that horizontal off axis FR measurements are almost always done in 15 degree increments up to 45 degrees. Every speaker review I have read does that and even the existing measurements for the 170s and 340s do that - it's basically the standard. With these Sierras, you're only showing 5, 10, and 15 degree measurements horizontally......that's not really much of a test me thinks. If a speaker's FR changes much over only a 15 degree window, you better use a heck of a lot of toe in and keep your head in one spot