hi,i've seen many cover in youtube that the backing tracks have the singers' voice too!
so how do they make these backing tracks?all of the sounds even the voice of the singer is in the backing track except the lead
There's some backing tracks that are really rare with lyrics. Check my youtube channel, I have a Crazy Train and a Welcome to the Jungle video with backing tracks and lyrics. For the Crazy Train one I found, someone ripped out the "practice mode" track or something from guitar hero. So it still had the lyrics, but not the guitar. The same could be said for the Jungle one as well.

So basically you don't "make" them. From what I hear, people just rip them from guitar hero.