if you don’t know where you are going, any road will get you there....
i would say start with a deep love of live unamplified music so you have a reference, chasing your tail otherwise
research the physical and mental ways in which we hear - for example as a designer do you believe human hearing is more/equal/less sensitive to time information vs amplitude ?
system objectives come next which might with thought provide what we call the balanced trade space: cost , size, efficiency, full range, portable, etc....
then develop some design principles like : pre-ring should be avoided, wavelaunch that looks like the test signal, pistonic behavior in the driver, breakup x cycles away from crossover, cabinet nodes x dB down
probably a decent book in this, might look like designing, building, testing , and improving over time an airplane....
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