"Intersection" of multiple tracks?

I have multiple audio excerpts with the same background music in all of them, but sound effects layered on top of it (not the same with each track). Is there an easy way to get the “intersection” of all these clips, i.e. the background music alone? (Or, you know, something approaching that) And if there isn’t an easy way, how would you recommend that I go about trying to do it manually?

Are they MP3 clips? If they are, then the background sound is different in each clip and you can’t use the cancellation/addition tricks. MP3 rearranges sound depending on the total sounds in the clip. It gets the most file size reduction this way.

It doesn’t sound like it’s doing anything serious and that’s the trick of MP3—invisible processing—but sometimes it’s enough to throw off volume settings and it really messes up post production effects.


It’s sound from a video in mp4 format, which…I assume means the sound is encoded in MP3? I’m not an expert with that stuff.

I assume converting to a different audio format wouldn’t help either, right?