Equipment Stand placement?

My experience is exactly consistent with Megasam's and Cornfedboy's. Another principle is to move your rack away from the wall. Bass tends to stack up along walls and will energize the rack and components placed there. The performance of my turntable was greatly improved by moving the rack to the side (5m of balanced IC from pre to power) and about 1' from the sidewall and 5' from the back wall. This was recommended by the guys at ASC when they were helping me with room treatments. I also added Sonex foam behind the rack.

What I did to improve this was to use 50 Hz and 100 Hz test tones + SPL to find the lowest response place close to my speakers.
Guess what? in my room it happened to be between my speakers
behind their plane about 1 ft. My equipment is in separate tweaked sand box(45lbs) /inner tube boxes 1 for preamp, 1 for digital source and 1 for the amp. Results very good. Height with each is less than 12 inches
Good luck.

Several good experiential opinions are offered above, none exactly alike. KT what that tells you is, like everything else, you'll need to experiment in order to determine what works best for you with your own equipment in your own room. I also realized significant benefits by not having anything placed between the speakers so my rack is along a sidewall. However regarding my particular component synergy, I also found that longer interconnects were detrimental compared to shorter ones, while longer speaker cables resulted in less degradation than with longer interconnects & shorter speaker cables. Note that I prefer networked speaker cables, so those longer lengths are accordingly inherently compensated. The equipment rack, also containing a single stereo amp, is now all on a sidewall. In this way I was able to use shorter AC cords as I wired a dedicated AC line directly to the rack location, & my AC conditioners are also located there locally.
Again, all of these advices tell you not a whole lot about what will work best for your setup, but do offer many good suggestions about what might be most advisable for you to try out.

Thanks to all for your helpful replies. Bob - you're right - this has confirmed that experimentation is the order of the day. Currently, I don't have any choice as to placement, but soon I'm going to be able to free up one or the other side walls, and ultimately there will be some remodelling. I was curious if there was any sort of consensus as to the best approach but, like everything in this hobby, it's not that easy :-)