I have heard and read numerous accounts or people who have experimented with two different boxes. None have really been happy with the results. You could however, try something like building a small ported box and create a plug for the port. Play around with both sealed and ported and see what you like. You may determine that you prefer ported boxes when listening to pop-type music and sealed when listening to rock. I wouldn't, however, recommend going with a ported and a bandpass.
