Phase invert to remove bleed in 2 mono tracks

dwdavedw

Logician
I have 2 mono tracks, 1 Acoustic Guitar DI, 1 Vocal mic. I'm trying to remove the guitar bleed in the vocal mic. Tracks were recorded simultaneously (and have not been moved), Vocal mic was set to hyper cardiod and positioned as best as possible to reject the sound of the acoustic guitar. I inverted one track and played them - no plug-ins on either track, tried adjusting volumes of tracks - does not seem to have any affect. Any ideas on how to accomplish this? And/or ideas on recording methods to get better separation? I need to do a bunch of these setups- acoustic guitar and vocal and be able to work on each track separately.
 
Cancelling out by phase will not work. A microphone records a piece of air about the size of a coin and it does not know about voices and guitars. Your brain hears the same voice and instrument, but the two mics were in different locations and recorded different air vibrations. Maybe you can do something with some good reparation software, but I am not familiar with that.


And/or ideas on recording methods to get better separation?
There is one recording technique that can give you good separation:
Take two figure-8 microphones. When you look at their polar pattern, you see a dead zone in the middle, which is the plane of rejection. Imagine it as a very thin infinite disk. In that zone, a figure-8 mic is almost deaf. Deafer than the rear side of any cardioid mic.

Mic positioning is best done with closed headphones. Hold the guitar mic so that the edge of the imaginary extension of the "deaf disc" points to the singer's mouth. While keeping this position, you can turn the mic to get a good sound from a hot side. You do the same with the vocal mic, only there you point the edge of the "deaf disc" at the guitar. It sounds complicated, but at most figure-8 mics the dead zone goes straight away from the top of the housing and lies in the same position as the capsule(s). They are relatively easy to align. Of course, you need to minimise direct reflections around the setup. That's not nice for guitar, but well, there's no free lunch ...

I learned this technique from Michael Stavrou's book "Mixing with Your Mind" (highly recommended), it describes a lot of recording setups for various instruments and vocals.
 
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As has been mentioned, this will not work.

The sound of the DI'd guitar is completely different from what the mic picked up, pointing somewhere else, no less, so you can't substract it from the mic bleed.

In any kind of live recording (where more than 1 instrument is recorded at the same time, with bleed between the tracks), you're much better off to do several takes and then comp the best performance from these, so you cut from take 1 to take 5 simultaneously on both tracks.
 
A little bit more info and a possible solution I've found: This is for a video, so sync is important . I'm intending to double the vocal and clean up pitch, I put it into the Audiostrip website and got a clean vocal back. I can then use that clean vocal to align with a new recorded vocal, and mix and process that clean track. I'm really amazed at how clean the stripped vocal is, really incredible. Since I just need it for timing, not worried about the quality. Free version is limited to MP3, which is fine for my purposes. I think this is gonna work for me.
 
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