You know the read-heads that all tape players have? The half-dome metal piece that makes contact with the tape and converts the magnetic signal on the tape into electrical signals?
The adaptors have ANOTHER one of those, “wired backwards”, inside a fake tape – that converts the electrical signal from the CD player into a magnetic signal.
So the player is basically one of those heads reading the “tape” normally, but in this case it’s actually reading ANOTHER one of those heads that’s pressed up against it, and that’s inside a fake tape doing the opposite job to normal.
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