The Shure A15PRS permits instant switch selection of either normal or reversed phase (polarity) in any balanced line (including microphone or line level) cable. The phase reverser can also be used to connect unbalanced high impedance microphones with the "hot" conductor on pin 3 to inputs with the hot connector on pin 2 or vice versa. The A15PRS is symmetrical and can be used in either direction.
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