This post focuses on a technique for the tricky task of recording guitar and vocals at the same time.
One of the classic tricky engineering situations is recording guitar and vocals at the same time. Generally they bleed into each other and effects that make the guitar sound good make the vocals sound horrible and vice-versa. There are a number of things that can be done to isolate the two, including using a DI for the guitar, but I’ve found that there is only one really good mic arrangement that gets the job done.
You will need two figure-8 microphones. Place them directly in front of the performer and at 90 degree angles to each other, one pointing down at the guitar and the other pointing up at the mouth.
The cool thing about this arrangement is that figure-8 patterns have the best off-axis rejection of all the patterns and, if placed right, the two sound sources will line up directly with the area of greatest rejection of the other mic. One thing to bare in mind is that figure-8 mics will capture more of the room sound. They also will have a greater proximity effect, generally. Try to avoid placing this arrangement in front of a wall, as the reflection from the wall will end up in both microphones – out of phase, no less. That would sound pretty bad. Place the performer in the middle of a room or with his back to a non-reflective wall. Also, you may want to put a rug down under the performer to prevent gross high-end reflections off the floor in the guitar mic. Hopefully the ceilings are high enough to void this with the vocal mic.