The cliff effect is when a digital signal (music/photo/video) 'falls off a cliff' when it fades out because the receiver can no longer tell which part of the wave is a digital 1 or 0, and there are more errors than can be corrected. The output of analog signals will get worse and worse in quality as it fades out and fail gracefully. This is especially a problem with digital cell phones because, rather than getting a more staticky call, it just drops the call completely.
A scratched vinyl LP record will still play, though at reduced quality while a CD will suffer the cliff effect when even so much as a fingerprint gets on it.
by Wm. Wallace The Freedom Fighte February 8, 2009