Isolating drum tracks from an already mixed song

[cslaven]

Hey, everyone. I'm new here. I registered just to ask this one question really.

Here's the situation. A while back I had someone record drums for a song I was working on. They did a good job, but they sent me a wav file with the drums already mixed into the song rather than a separate stereo drum track or the raw tracks from all of the mics. The dude didn't charge me, and I don't know him that well, so rather than ask him to send me separate drum tracks, I was trying to figure out if I could isolate them myself and then dump them back into my DAW for mixing into the song. I tried some eq and canceling techniques used for things like vocal removal/isolation, but I didn't like the results. Even when I got to where everything but the drums were relatively muted, the collateral loss of quality in the drum sounds made the track unusable. (They also sounded like they had a phaser effect on them for some reason).

But then it occurred to me that I have the original song (without drums) and the one he sent back (with drums), and I started thinking that there might be some kind of processor that compares two tracks and automatically removes duplicate sounds, leaving only what's unique about the second track, in this case the drums. You can easily do this kind of comparative analysis and negation with two images in something like Photoshop, so I thought there might be something analogous in audio editing. If this is possible or if anyone knows of another way to isolate drums in a mixed down song, I would love to hear from you.

Thanks!

 

[JimmyS1969]

Not possible likely in any effective way. Drums cover the whole frequency spectrum. Not going to get good results.

Ask the drummer to send the separate tracks. Not sure why he didn't to begin with...

 

[jkuehlin]

If this is possible or if anyone knows of another way to isolate drums in a mixed down song, I would love to hear from you.

Thanks!

I can do this. Private message me your email. I'll need to hear the track first, but there are some ways this can be done without causing any frequency or phase alterations to the non-drum content.

 

[Guitargodgt]

Even phase reversing the track without drums with the one that has it will still cause some goofy phase problems.

If at all possible the best way to get this done is to ask for the original drums.

 

[JimmyS1969]

I can do this. Private message me your email. I'll need to hear the track first, but there are some ways this can be done without causing any frequency or phase alterations to the non-drum content.

You are either a magician or offering of replacing the drums with samples.

 

[bouldersoundguy]

If the two versions are the same mix and the only difference is the drums, it may well be possible to invert the polarity of the original and subtract it from the one with the drums. Things that would interfere with that would be any dynamics or eq applied to one and not the other, or if the sample rate was changed between the two versions, or if the one with drums is a compressed file.

 

[Farview]

Other than the phase reverse trick, there is no way to do it. It would be like trying to turn cake back into flour, eggs, water, etc...

Once you mix things together, it turns into something else.