"If it's working you will not hear anything - the music will keep on playing." Those are opposites, New. If the loop is working, Licorice will indeed hear something, since the music will continue playing.
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Tape Loop Testing On A Preamp?
I have an old NAD 1155 preamp whose tape out loops appear to have ceased outputting anything. It seems strange to me that both tape loops would crap out at exactly the same time (common circuit?), but I am trying to find a solution, and/or a test for the tape loops that proves they are either dead, or alive.