Just want to share results of my recent experiment with adding rake (tilting speaker back) to my floor standing speakers. When I owned a pair of R50s, I never heard about rake on speakers until recently.
I have a pair of VA Bachs for a few weeks now. They sound pretty good but not great like I heard when I audtioned them at the seller's home. So this week I started experimenting with rake by raising the front the speaker fractions of an inch. For my seating position about 12 feet away, raising the front by 1/4" completely changed the way the speaker sounds. The highs and mids blended much better, and the midrange now sounds incredible. Bass also improved too. I tried 1/2" too but that was too much because imaging became a problem.
I'm curious if Polk floor standers could benefit from rake. Anyone with Polks ever try? If you haven't, you might want to try it and see if I improves the sound. Just wedge something to the front footing of the speakers such as wood or stacks of quarters.