I assume that everyone already knows the importance of phase matching a sub to the main speakers
Um, no. Not at all. Physical impossibility. Neural impossibility too. Absolutely positively zero chance this is important at all. None.
Flies in the face of physics. Sound travels at a rate of about one foot per millisecond. The wavelength of sound varies tremendously by frequency, from as short as an inch at very high frequencies to 50 feet or more for low bass. Sound travels in waves. Waves are reflected, refracted (bent, diffused), or absorbed according to their wavelength and the size, shape and composition of whatever they encounter.
Got it? Okay, so we play music all these waves start bouncing around the room. Forgot to mention, when waves meet they either cancel out or reinforce each other. Very important. Sounds silly basic but crucially important you understand these points.
So a sub, it puts out 80Hz and below. Waves 20ft, 30 feet and longer. Most of these waves are longer than the biggest dimension of your room. What this means in practice is a low bass wave emanates from the sub, encounters a wall, and is reflected right back to the sub, all of which happens before even one wave is complete! The sub is canceling- or reinforcing!- its own output!
This never happens with midrange and treble frequencies by the way. Unless your room is really tiny, like closet size, then you have other problems but not the cancellation/reinforcement problem.
So you see it cannot possibly matter where a sub goes, at least not in terms of what you think, phase matching. No such thing. Impossible. You can see that now, right?
Next problem, neural or psycho-acoustics. Very low frequencies do not register as sound at all at anything less than a full wave. At 20 Hz that means 1/20th of a second to hear that frequency at all. We know a 20Hz wave is more than 40 feet long. You can look it up, I'm getting a little bored explaining all this for the umpteenth time. Point is, it cannot possibly matter where the sub goes for the simple reason your ears cannot even register its output fast enough to locate where it came from.
Even if you don't buy the science, which a lot don't. Most people talk about how they respect science, when really they go with whatever the most people are saying. In other words not thinking at all but following. This information will do you no good whatsoever if you are a herd animal, it is only useful for thinking beings.
All thinking beings know from experience you cannot tell where the sub is located. If you somehow screwed this up come on over, happy to demonstrate. Everyone is shocked to look around and see FIVE subs randomly spread around the room, all pointing away from the center, all within inches of the wall. No idea whatsoever that any bass at all is coming from them.
If phase matching mattered at all the bass in my system would be horribly chaotic. When in fact it is gloriously clean, articulate, and absolutely beautifully integrated with the midrange and treble.
But only because I, unlike "everyone", understand the unimportance of phase matching subs.
