“The Real Song for the Deaf”, which is essentially Track 0, is located in the pregap of Track 1 as a hidden track. The hidden track can be found by rewinding the first track to roughly -1:33. A voice comes on and says: “Huh? What?” and a pattern of low-frequency bass plays and modulates for the rest of the song.
This track […] is difficult to listen to on all but conventional CD players. Most software CD players do not allow rewinding of this nature, and most MP3 “ripping” software will not include the data.
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This is so fascinating, I wonder if other types of medium of similar methods for hiding music.
People have done this with vinyl by putting hidden tracks on second grooves not connected to the main groove.