[net.audio] Whispering ghosts

ryan@fremen.DEC (12/14/84)

	On some records (if the record company is trying to cram a lot
of music onto one side), the pre-echo you're hearing may come from the
next track.  However, the usual cause of this is bleed-through on the
master tape.  Since the signals on tape are magnetic fields, they can
affect the signals on adjacent parts of the tape (the next revolution
on the reel).  The bleed-through effect is strongest moving towards the
outside of the tape, so storing the tape "tail-out" (that is, so it must
be rewound before playing) makes the bleed-through come after the original
sound and it is thus masked by the music.  If you here anticipatory
ghosts, that means the engineer was lazy (although they are helpful in
cuing a record track for taping...).  You can tell for sure whether the
cause is the record or the tape simply by seeing if the ghost is audible
exactly one revolution before the actual beginning of the track.
	Mike Ryan