I have one of my speakers positioned between a wall and door opening-its only about 100mm off the wall, it's not ideal and I get bass boom. The article has made me think how I could improve things. I will try moving the speakers but wont be able to get them in the middle of the room like the article suggests.
Jerry
Hifi: IPL transmission line floorstanding speakers, Squeezebox Touch, Denafrips Ares 11 DAC, DCB1 Pre-amplifier, Croft Series 7 power amp.
Custom Hifi cables HA10SE headphone amplifier and Hifiman HE-400 headphones.
AV system: LG 55B7, Denon AVR -x2300w receiver, Quad 12L (front) 11c Centre and 11L rear . Velodyne DD15 subwoofer.