Hi Would anyone be able to help me with mounting suggestions for these speakers? My walls are 1" plaster and render followed by 4" blocks. Behind the blocks is the heavy duty sponge insulation. I'm going to channel out the required size but I was wondering if I should just cut straight through the plaster/render and the blocks so that the in wall speaker would be backing onto the wall insulation. Or would it be better to have the back of the speaker facing the block which would mean much carefuller channelling out. What I am trying to get at is, is the sponge or the block better for giving better sound or am I worried about nothing?