“When starting a remix, the first thing many people do is put the vocals into Ableton Live to manipulate the timing. But don’t expect to just put in the old and new tempos, sit back and have it all done for you. Don’t stretch what you don’t need to stretch.
“Try to preserve as much of the original tempo as you can. When using any ad-libs cut them tight and place them at original tempo. Try not to slow down anything that doesn’t need to be slowed down, especially sustained notes at the end of phrases. Why make it sound bad when you don’t need to?
“In the same way, if you’re speeding up a vocal then the end off phrases don’t need to be sped up as much. If you take this approach it will help preserve the character and vibrato of the original vocal.”