RCF/Mackie ART speaker series question
 

Hi all,
I'm much involved with pro audio repairs like active speakers and
such.
I've had quite a few of those classic RCF (today Mackie) active
speakers, model ART300A with blown speaker elements.
Some collegues of mine also have this experience. It seems like the
built-in amplifier module has the power of blowing the speaker! It
also includes a limiter which will avoid heavy clipping, so I don't
think clipping is the problem either, (as long as it limits).
Recently, I had an ART300A with a blown low-freq. element, the amp was
still intact, hook up a dummy speaker across the output and amplifier
performs as expected. No DC or any high frequency oscillation.
Replaced the original speaker element and the thing was completely ok
again.

Does anyone have any valueable information regarding this matter?

What's going on inside those ART active speakers, really??

Best regards
Stefan