r/livesound • u/Vichaama49 • 12h ago
Question Smaart measurement questions
Hello World, this week I have calibrated a system for a small event. I'm familiar with Smaart and other calibrating tool. I have already seen this king of measurement but I doesn't know why it's happen : a small phase rotation at the crossover section.
I join some pictures of the mesure I made, the physical thing is in the red circle.
To resume : One RCF Art 915-A for the Top and TP218/1600 A (Thomann) for the Sub.
Crossover made with a DBX PA2 cut at 115 hz (LR 24)
The phase rotation appear and disappear with the mic position, but the majority of time the rotation is present as we can see on the third picture : 3 positions to made the average and the rotation is present.
I think it depend on the type of filter ( LR / But / 12,24 etc ) but it's change nothing to very little difference to the phase, and always on the cutoff frequency.
SO, here my question : how is this happening ?