Think of it this way. The weird phasing issues that occur when you stand up from the mix position is happening every time your head moves at all left to right. Comb filtering, masking etc...
The only reason to put speakers horizontal is really to make more vertical room for far fields, and reduce reflection from the near fields in this regard.
Is it ruining your speakers? No. Just keep in mind to stay in the sweet spot as much as possible.
Last edited by MickeyMassacre; 17th September 2011 at 07:29 PM..
Reason: One more line.