Animation Music (not like the others, I think)

[MConte05]

Ok, we are in a tight spot.... I made a 30-second music clip using Goldwave, it fits perfectly with my animation. Anyways, what I did was use 5-15 sec clips from different songs (Thousand Foot Krutch "Rawkfist", Yellowcard "Only One", and Black Hawk Down Soundtrack "Chant"). I modiyfied the songs beyond reconigntion (took out lyrics, increased bass, crossfades, fade in-outs, etc.) and I am wondering if that would count as an original peice or do I have to obtain the copyrights for each song?

I always thought that if you use clips from songs then you don't have to pay copyrights or anything (since radio stations do this with 20-30 sec "hooks") and that if I modifyed them so much that it sounds like one song, then its fine. But its confusing....If length does apply, then these are the lengths that the songs are used in the animation:

"Only One" - 6 secs
"Rawkfist" - 15 secs
"Chant" - 9 secs

Anyone please respond quickly, I already searched the boards and tried searching the BMI website, but nothing clear came up....