"there has to be more of a precise definition. otherwise it just becomes anything about ghosts or memory. which is entirely too vague and largely meaningless."
OK, to bring it back in a little...
I was thinking on the way to work this morning that one of the reasons for the Ghostbox/UK memoradelia sound is bcz the UK never had a real avant-garde/academic/contemporary classical scene that was both dealing with new technologies and was financially supported by the government/corporate finance. Instead of UK equivalents of IRCAM or Darmstadt we get the Radiophonic Workshop who are working with similar techniques but in the service of doing TV themes and incidental music. After leaving the Radiophoonic Workshop, their founder Daphne Oram makes Listen, Move and Dance, a seven inch designed for primary school kids to do free movement to. Other people with interest in tape techniques, like Basil Kirchin, end up on prog rock labels or doing horror film soundtracks. (Even people like Trevor Wishart who do work in universities have a daft space-age quality to their work that makes them closer to Joe Meek than Stockhausen.) That these people's work ended up in places where kids would have to hear it (schools science programmes etc.) or would actively seek it out (horror flicks) means that the UK has a weird, queasy relationship to this type of sound that is profitable to work with.
(Hey Mike Powell! Good to see someone else Stylus on Dissensus.)