I use Zapco DSP-Z8 with Zapco Power Amp i450 and ST5X to drive 2HF, 2MF, 2LF, 2(Rear) + 1 Sub.
All DC connected, without x-over.
Problem happened if I switch the ignition to "on" (before start), and the system will power-up and working normally.
BUT... If I start the engine, the HF and MF speaker popping a very loud sound.. and after 2-3 times like this happened, my MF speaker broken.
Any suggestion to prevent loud popping when I start the engine from stable "On" condition.. (i.e. you park somewhere, and listen to the music without engine running, and suddenly want to start the engine)