what are some good microphone setups for recording a single singer/guitar player with two microphones? Position, types, levels, etc. Thanks!
Your big problem is that the guitar is going to be all up in your vocal mic and vice versa. To minimize this:
Get the mics as close to the source as is practical. You'd like to get the vocal mic right on the singer's mouth and the guitar mic as close to the instrument as possible (I like 12th fret usually but lower bout is also good, and a bit further from singer's mouth). Performer technique will be your limiting factor here.
Choose mics with the right patterns. A figure-8 on the vocal, pointed up at the mouth a bit so that the side null points to the guitar, will reject the guitar pretty well. A tighter pattern on the vocal mic will help in any case (hypercardioid instead of cardioid)
Be careful of reflections. Record in a relatively dead space; use spot-treatments to kill direct reflections that you can see
Watch for phase cancellation problems, especially if you can't get the mics close to the sources (remember the 3:1 rule)
OR, quit fighting to separate your sources, you will just be frustrated anyway. Record with an MS stereo setup, carefully positioned to balance guitar and vocal the way you want it. Get a good-sounding room, take your time setting up, and hit record. Done and done.
I remember watching a Dave Weiner Riff of the week about recording acoustic guitar:
He goes through mic choice and placement for different sounds.
Placing the mic near the sound hole gives thick sound with lots of mids and lows, whereas a placement near the middle of the neck gives all highs.
Ideally you would use a mic at each position and then mix the output, giving a good harmonic range.
I like recording the guitar by capturing the input from a mic like an SM-57 at the soundhole as well as the pickup, if the guitar has a good pickup. That gives you a better spectrum of sounds to choose from later when mixing. Experiment with angles until you get a balanced sound, but you'll need to position the mic so the talent doesn't brush the mic when picking and strumming. For vocals, whatever mic the singer prefers close to their mouth will be fine, hopefully one that's fairly directional.
You don't say if this is live or in the studio, but it shouldn't matter that much when recording vocals and guitar together. If this is a live-in-the-studio situation, try using a condenser mic to capture room sounds in addition to the above. (In a performance situation, a condenser mic would be overkill to capture crowd noise.)
A couple more possibilities...
You can make use of a microphone's polar pattern here. Of course they all have their dead spots, and depending on what's comfortable, you could probably use a few different ones to accomplish your goal. Cardioid and Figure 8 come to mind.
Imagine using two mics, both with a figure 8 polar pattern. If you oriented the vocal mic such that the guitar was at 90 or 270, you would get quite a bit of isolation. Likewise with the guitar mic.
Yet another possibility is to put a baffle of some kind between the vocal mic and the guitar mic.