In most consumer home theater applications, the length of the speaker wires do not have to be the same and most receivers that have the YPAO microphone setup feature can compensate for small delays, if there are any. Manual adjustments may be needed if a delay is noticed during playback. In order for the human ear to notice a delay, the cable length differences would have to be very large. Example: Front left 200 feet and Front right 3 feet.
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