Yes you can phase switch (or just connect in reverse one of) the tweeters to reverse phase (usually the closer) so it acts out of synch to the other thus altering the time the wave takes to reach the listener, however this makes it absolutly crap for the passenger with marked phase shift in the stage.
Better to have a time shift processor (alpine ued to make one, so did alesis) that had fied mics installed and sampled the vehicle and adjusted the outputs to each speaker according to the selected number of passengers and their seating location. Such tech, the ability to perform quality installs and good knowledge seem to have disappeared along with my desire to share much of my knowledge as todays youth don't want to learn, when they can pay for the afore mentioned crap.
Ask me how to make 100dB + from <50w and one speaker.
Bookmarks