A couple posts ago, there was talk that placing 2 mics on an amplifier can produce exciting nü tones. Wait… what if we can only afford 1 mic, Mr Money Bags?!
Alright, time to hit the essentials last. Better late than never, though…
So pictured below is a diagram of a speaker from a guitar cabinet. Usually you only have one speaker … don’t try to mic an entire Marshal 4×12 cabinet with one SM57. It just don’t rock… Choose just one speaker (as pictured here).
Mostly what we want is a small, single speaker boutique amplifier… it sounds better than Direct Injection any day.

The cone of the speaker is exaggerated, but you get the idea. It produces the most high end, and therefore the tone is “crisp” near it. If you listen back to your recording, and it seems like the guitar tone is a little muddy try moving the mic nearer the cone, away from the speaker’s edge. The further off center the microphone is, the more mellow the sound will become.
Now how far away from the speaker should the mic be? I’d say about 4 inches.
Also, you will notice that I have placed my SM57 at an angle. I’ve found that this adds a touch of high end air to the sound.
The 57 handles guitar quite nicely. Electric guitar is almost always recorded with a dynamic, cardiod mic. What do those words mean? We haven’t had posts just yet on them… so here are the Wikipedia entries, because we know that you are going there any way!
Dynamic Microphones
Cardioid Polar Pattern