Very important Sam?

[ogs]

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SAM changes the balance between the bass and the midrange, simply because it corrects phase below 150 Hz and provides additional bass extension.
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In fact, I'm pretty confident in saying (it was mentioned on the forum some time ago), SAM corrects phase across the whole frequency range and not just below 150 Hz.

That may be correct for some speakers, but when Maxime from Devialet did measurements for SAM on my speakers I brought only one box without the tweeter. He measured the bass/mid through the dividing network (a series inductor of 0.86 mH and a RC across the driver of 20uF/8R2). That indicates that the SAM correction is active up to at best 1.5kHz. Diagrams I got from Maxime afterwards indicate that correction stops between 200 and 300Hz.