In my 35+ years of designing, I really don't think there is "one single person" that is the designer, master of all. There is just too much going on for one thing, and there are too many trades to get a handle on to be a one man band.
In the groups I have been involved with, there were the mechanical folks, electrical folks, chemical folks, finishing experts and then one guy to overlook the project as the lead. He kept all the monkeys from going off in the wrong direction, much like an orchestra conductor.
In my lighting career, there were those same kinds of folks, plus photometric people and manufacturing people as that place was also a manufacturing facility.
Of course, bean counters showed up as well as purchasing people and if it all went south, the CEO showed up to look stern, then re-assure everyone that they need to bust their balls to get the project done.
In the case of audio, I think a good designer knows what he wants and tries to steer the ship to that ultimate goal. That is the key to success, keeping all the "genius" mechanical, electrical and other dreamers focused on the same dream. Again, back to the orchestra and the conductor. Play all the right notes at the wrong time and you got crap. Play them at the appropriate time and you have music.
Wayner
