Why does pulling out main speakers from wall improve sound?

Some Great Explanations Here…

or your Dealer is either “pulling-your-leg”

…perhaps didn’t understand your question…

failed at a bad joke…or is on “the” CracK. 

 I assume that because bass spreads out in all directions - 360 degrees. Being too close to walls increases the bass as well as muddying the sound. 

From Physics I seem to remember that sound waves reverse phase every time they bounce off a hard surface. I've put on a signal generator for various frequencies and tracked results using a handheld sound pressure level meter to measure changes in volume as I've moved the speaker. My best guess is that the sound waves reenforce at some spots and frequencies and (try to) cancel at other frequencies at the same spot. how significant is this? Not very. All said and done, the direct radiation path is more significant than all other indirect paths in my small room. I don't argue; I just listen.

While responding to another post, I was reminded of the Dutch and Dutch 8C. They address the issue in a different way:

1) They use mainly acoustic methods to present an out-of-phase "midrange" signal at the sides, to cancel the midrange as it is "wrapping" around the cabinet. Quotes around midrange as it will be frequency controlled.  This would replace acoustic treatment with a traditional speaker.

2) They accept boundary reinforcement in bass frequencies and provide DSP correction, something that can be done with any speaker.

In my opinion, listeners should just listen and make up their own minds. I think the problem in audio and other subjects is that people have too many premeditated ideas based on things they just read rather than just listening. Who cares if it goes against things people say. I've been in many situations like that on all fronts. I'll give an example. Many audio buffs say not to place Klipsch Forte's against the wall. I have two videos in two different rooms. Yes, they are two different rooms but one is treated professionally at Upscale Audio, has the newer version of the speaker, which according to others,is supposed to sound better. 

Even though YouTube isn't going to produce all the fidelity, it still offers a "relative" difference between the two different rooms regarding placement and sound which is clearly audible with earbuds or headsets if one listens. You be the judge. 

The Upscale Audio Forte IV's are placed several feet away from the back wall while the Forte I's in the second video are about 1 foot from the wall. 

Skip to 4:00.