Originally Posted by
davef
For an MT speaker it is all about optimum integration between the tweeter and woofer. With crossover design, that would not change whether the speaker is positioned vertically or horizontally.
With an MTM like the 340 (with large diameter woofers), when positioned horizontally the designer must do what he can to limit off-axis lobing - one method is to lower the crossover point. In addition, with the 340 center, we put additional optimizations in place to counter the effects of having an extended baffle that is created with placing the speaker on a console, typical of center channel placement.
Depending on the design of the tweeter, it may or may not need to be rotated.
Hope this makes sense!