How far apart do you position your speakers ?

Hi Mofimadness,
Ear height, center of panel.

Timlub,

Thank you sir!

The 83% rule doesn't seem workable in my room. Is there any theory behind it? It seems a rather arbitrary number.

I have no symmetry in my room, so I try to keep both speakers and my listening position at least 4 feet from any boundaries, since I can't even up any early reflections by symmetrical placement.

I sit about 10-15 cm further from my speakers than they are apart (about 2.56 m). I find I prefer my Vandie Quatros to be at least 8 feet apart for soundstage width. I like to be close enough for an immersive soundstage, but not so close that it becomes "heady".

Daverz,
As I stated above, I hadn't heard of it either, I have done many set ups recently and did the math after reading this thread. You will also read that I went back to the Cardas Method. I really recommend that you start there. Many have talked about the triangle, but there are several room measurements that help your speakers placed correctly realative to room boundries. I figured every one of them before placement, my finished results are very good. This doesn't work for everyone, but it has a very high success ratio. I have attached the web page below.
Good luck, Tim

http://www.cardas.com/content.php?area=insights&content_id=26&pagestring

My room is too irregular in shape for any geometric speaker placement method to work, though the irregularity may also work to break up modes.