I have a Vox 4 X 12 cab. I have an SM57 which I know is probably the best mic to use. However, are there any special techniques for getting a better sound from the mic? I believe that it is better to tilt the mic so it is not facing straight into the cone. I have some other condensors too, would it be beneficial to throw one of those behind the 57?
For now, work with a single SM57. Multi-mic setups add a whole slew of other problems (phase cancellation, for one), so initially it's probably best to learn the fundamentals of positioning with just a single mic, and add more complexity as you go on. and, honestly, the majority (probably - no hard numbers to back this claim up, but I'd be shocked if it isn't true) of guitar recordings you've heard were probably done with a single SM57.
After that, experiment. There's as many good ways to record as there are good recordings, and the best way to get good results is just to spend a lot of time trying different positions.
The way you've suggested (point a mic straight at the center of the cone, maybe 2" back, and then angle it a bit so it's parallel with the 'wall" of the cone) is certainly a valid way to go (I think it's Slipperman's go-to in that excellent tutorial of his floating around the net), but it's definitely not the only way. I tend to point a SM57 just shy of 2" back, parallel with the grill of my cab, and a bit off center, closer towards the edge of the speaker cone than the center.
That said, the best way to go here is to fire up your amp, strum a chord, and while it sustains swing a mic back and forth in front of a speaker while listening back through headphones set for real-time monitoring.
One word of caution - initially your ear is going to prefer brighter, edgier sounds, since they're going to be percieved as louder and more powerful. This isn't really true, and a lot of the time it's the darker sounds that work better in a mix.
