To respond to: Wuzzer, Idontknow & PeterP ---
My room is an irregular shape. it’s roughly 15’ x 15’.
i have the the Low Pass Filter set to 60 and the Slope at 24 dB, which SVS recommends for Heresy IVs. I have the volume set at around -6 or -7 for music. The blending is seamless to my ears. I listen to a many different types of music but mainly Jazz, Folk & Rock.