These are some links to sites that have been posted here and otherplaces. I thought I would post this as I felt osme of you might find it interesting.. Happy reading... Kurt
http://www.AKG.com/AKG_structuretree/powerslave,id,39,nodeid,,mynodeid,39,_langauge,EN.html
http://inventors.about.com/library/inventors/blsoundrecording.htm
http://www.robertmargouleff.com/publications/surround_1099_fig2.htm