you cant make one without affecting the song. most softwares
inverse the song signals(or frequencies or watever, cant rmb) so as
to get rid of the similar sounds from both channels of the song.
since the vocals are in both channels most of the time, it gets cut
off. but parts of the background music that is similar from both
channels will also get cut away. the result will be a song that
sounds very supressed and you will notice some instruments missing
from the background music
Conclusion: go get the original KTV VCDs. or some singers like
Ocean Ou have the -1 versions in their albums
