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Hi, I'm having some trouble isolating vocals in Logic Pro 8. Basically I have an original mix of a song in one track, and then in another track I have an instrumental version of the song. I invert the instrumentals phase, but then I have no clue how to combine the instrumental and original track on logic so all I hear is the vocals. I've tried the merge button I've tried just dragging the instrumental onto the vocals, but nothing works. Ideas?

Playing them both on parallel tracks would effectively merge them. You don't need to actually 'merge' two tracks together. When you're done, just bounce down the mix.

I'm not sure what you're trying to achieve here so it is difficult to offer more advice.

X-Trade wrote:Playing them both on parallel tracks would effectively merge them. You don't need to actually 'merge' two tracks together. When you're done, just bounce down the mix.

I'm not sure what you're trying to achieve here so it is difficult to offer more advice.

I was trying to get only the singing for the song 'Like A G6'. I have a version with the music only, and the full version which had the vocals. I had hoped to invert the phase of the instrumental to make the full version have only the vocals.

However, I found a vocal track online so I won't need to do this anymore, although it'd still be nice to learn how to do it.

What I did is I created two tracks in Logic, imported the instrumental and original, then lined them up perfectly. I then inverted the phase of the instrumental in Logic's Sample Editor, but it didn't make the original disappear- the original's instruments still sounded. This is why I thought they had to be combined somehow.

It is possible that one of the versions is mastered or mixed differently (or not at all). for example if the vocal were higher in the mix any master compression may have responded quite differently, so even though they are the same song, same phase, same pitches, the volumes of the instruments at any time may not be the same at the same time.

Alternatively the instrumental may even be very similar but actually a completely different recording.


But typically, yes: place the same audio on two tracks, perfectly in phase, and invert the phase of one, you should hear nothing.

X-Trade wrote:It is possible that one of the versions is mastered or mixed differently (or not at all). for example if the vocal were higher in the mix any master compression may have responded quite differently, so even though they are the same song, same phase, same pitches, the volumes of the instruments at any time may not be the same at the same time.

Alternatively the instrumental may even be very similar but actually a completely different recording.


But typically, yes: place the same audio on two tracks, perfectly in phase, and invert the phase of one, you should hear nothing.

I'm fairly certain the instrumental mix was an official mix so I'd think it should be the same, but maybe the producers specifically changed some things so as to throw people like me off.

Would tinkering with volume as I play the song slowly take away pieces of the instruments?

I see very little chance you'll be able to do this, unless you're absolutely certain it is the same source material processed through excatly the same effects and vocals had no influence on anything else - just as x-trade wrote. I don't think they did something to 'throw you off', but - especially in the pre-digital recording/mixing era - it would be a very difficult task to produce two identical mixes with just a single vocal or instrument difference.

However, if it really is the same and all volume ratios and phase parameters align perfectly, then you should play with nudging (in protools, it should have some similar name in other DAW software, basically moving the selected portion of the audio back and forth on a sample per sample basis), rather than volumes (or both, actually, to find a perfect mach).

It is best to zoom in on the audio waveform and align a clearly visible transient (e.g. snare hit) the best you can on the two tracks - remember to observe the reversed phase. Then nudge left or right one of the stereo tracks until the sound gets thinner and thinner (basically as if you heard a filter being tuned towards the higher frequencies) - if the two materials are identical, at some point all else should disappear but the difference signal (vocals, in your case). You might have to fine tune volumes as well, if the two tracks are not 100% identical.

Again, I think you stand a very little chance that the two tracks are identical apart from vocals - but good luck, hope it will work for you!