How do I isolate vocals and guitar to their specific microphones?

Question

Hi, not a very good title so I will try to exlplain further here.
I am using Audition CS6 with multiple mic inputs, 2 mics to be precise, 1 to pick up acoustic guitar and 1 to pick up the vocals. I am then using multi-track mode and assiging each mic its own track. The reason being is because I want to use post editing on both guitar track and vocal track individually.
The problem is I am using 2 condenser mics so both mics are pretty much picking up exactly the same which makes post editing the tracks individually impossible.
I understand that both mics are going to pick up abit of what I don't want it to, eg, the mic specifically for the guitar is going to pick up some vocals aswell, but there has to be a way that I can minimise this. After all I don't want to record the guitar and vocals seperately.
Any help would be much appreciated.
Thanks

Answer 1

It depends to a large extent on your microphones.
Most condensers these days are a cardioid pick up pattern which means there's a strong pick up from the from the front and a greatly reduced one from the rear.  That being the case, make use of this pattern when positioning the mics--have the guitar mic up higher than normal and pointing down at the guitar so the area with less pickup is pointing at your mouth.
Do the reverse with the vocal mic so the null side of the mic is pointing mainly at the guitar.
Obviously this applies only to cardioid mics--if you have omnis, then not much you can do.
Second, make use of the fact that sound follows the inverse square law--get the vocal mic as near the mouth as possible and the other one near the guitar.
Finally, you don't mention what you're using for an interface but obviously make sure that things are routed so each mic is isolated to one track only.
Having said all that, for clean recordings, I'll often do a guide track with both voice and guitar, then go back and record the two elements again but separately.