Originally Posted by
GM
Ideally, you want drivers sharing some portion of a BW to be < ? WL apart at their -F6 point to ensure both good acoustical coupling and minimize comb filtering enough to the point where there’s no perceived ‘echo’/’smearing’ of the signal both on and off axis.
The reality of course is that it would take many drivers, XOs to achieve this over a wide BW, so all sorts of driver, speaker design decisions must be chosen to find an acceptable compromise.
Since the HF will need the least driver spacing, they normally should be positioned as close together and on the same plane as practical, though in your app, the XO of each speaker system should by design be ‘steering’ [tilting] the HF’s response upward to some extent due to being ‘lowboy’ designs; ergo ideally you would measure their individual polar responses and adjust the tilt of one or both systems such that they overlap at ~ear height at the Lp for best overall HF performance.
GM
