Slightly off topic is the destructive combination of the Soundcraftsman graphic EQ and the DC300. The Crown would cook speakers if the EQ turned on after the amp..or the cord kicked out then replugged.
The DC300 was notorious for eating speakers from steady state DC voltage****, not turn-on/off transients. While customers hated loud transients and worried about their speakers, actual speaker failures from power transients were pretty uncommon (with real PA speakers).
The first generation dbx driverack was widely panned for not suppressing turn on/off transients, but this is mainly a cosmetic or ergonomic concern, that dbx failed to figure out when they decided to enter the new (for them) market of live SR. Everyone already in that market knew and understood. DBX figured it out the hard way from hundreds of customers telling them, until they changed it.
JR
**** I have repeated this story ad nauseum but another old classic amp was notorious for clipping asymmetrically which imposed a DC component on loudspeaker voice coils and often premature failures. Peavey suffered many undeserved speaker warranty claims, until that other popular amp manufacturer cleaned up their act. (Hint it was related to their current limiting protection circuitry.)
