Phase Cancellation: Difference between revisions
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should not occur with units space more than about four feet apart |
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== Practical Note == | |||
"Finally, we have convinced ourselves that audible phase cancellation should not occur from two systems spaced more than about four feet apart. The combing is just too dense. So all of that makes sense." - Ken-at-Bose <ref>See: http://bose.infopop.cc/eve/forums/a/tpc/f/6806048934/m/7831003593?r=3291045593#3291045593 in | |||
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=== Theoretical Discussion === | |||
Running two inputs 180° out-of-phase puts the peaks and valleys of the sine wave so that they null each other out when summed (see the middle picture below). This has a tendency to cancel out both inputs, and is quite pronounced in the "far" field, but negligible in the "near" field. Normally phase cancellation is undesirable, but when you know what you want (and in this case, what you don't want) then you do it deliberately. | Running two inputs 180° out-of-phase puts the peaks and valleys of the sine wave so that they null each other out when summed (see the middle picture below). This has a tendency to cancel out both inputs, and is quite pronounced in the "far" field, but negligible in the "near" field. Normally phase cancellation is undesirable, but when you know what you want (and in this case, what you don't want) then you do it deliberately. | ||
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