If it was me I would stick with 80 Hz. Yes 100 Hz looks the best on paper but that's only if every channel is playing the same frequency at the same time, that is all channel "mono" in reality. I hope I am not confusing you.. For real world use, I suspect 80 Hz may work better for you.\n\nThe reason I asked to see all those curves for 40,60,80,90,100 Hz is to satisfy my curiosity\/am obsessed.. (sorry for being selfish!) about whether Audyssey would make the comb filter effects worse. From your graphs, as well as my, if would appear Audyssey did improve the comb filter effects at any crossover setting, though it worked best for the higher settings such as 80, 90 and 100 Hz.\n\nThat is comforting for people like me who is obsessed with specs and measurements. Thanks again for taking the time to do such time consuming experiment.\n\nBy the way, in your case it fully demonstrate the good thing about the App, as you can now save what you have now as the "reference" so you can fall back to it without having to start from scratch. From here, you can follow @Jon AA 's suggestions to shape the low end away from the current "flat to the end.." to something like the "Harmon target curve", unless flat is what you prefer, that apparently not most people prefer. Without the App, I would say AARC and Dirac Live are clearly the much better choices.\n\nNo problem. I wanted to see where you were going with it and it's gIves me some more experience.\n\nAnd yes, I really like being able to save multiple files and switch them in and out. It does save a ton of work. Here are the results of my tweaking.\n\nWhy did it change the scale?! I had it set at 5 dB increments. Here's the screen of the exact same chart.\n\n\n\nAnd some house curves!