Although there are some great acoustic pickups out there that can be indispensable when performing live, when recording in the studio (unless you get a James Tyler Variax guitar), there is just no substitute for a well-miked acoustic guitar. This is not hard to do at home, and the room you record in at home may sound better than you think.
CHOOSING A MICROPHONE
If you are recording any acoustic instruments at home (including voice), a large diaphragm condenser mic is a great investment. There are options out there starting below $100, and going up as high as you want to go. While some of these mics (especially the least expensive) may only have one pickup pattern (usually cardioid), several condensers (like the one I used for this blog) include switchable pickup patterns. Cardioid picks up sounds in front of the mic and rejects signal from behind the mic. Figure-8 picks up equally from the front and rear of the mic, while rejecting sound from the sides (useful for recording two singers into the same mic while limiting pickup of other instruments), and omnidirectional (or omni) picks up sound all around the entire mic. There is also often a roll-off switch for filtering out low frequencies around 80Hz and below, and a pad switch for reducing gain (to avoid overloading the microphone when recording loud sources).
I recorded the sound samples for this article with an M-Audio Sputnik tube microphone, using the cardioid and omni patterns. I did not use the low-frequency cut or the pad switches. For my audio interface, I used a Line 6 TonePort UX8, and my recording software was Propellerhead Record.
An easy starting point for recording acoustic guitar is to place the mic as close as you can in front of the 12th fret. In the first two examples, I have the mic about 3-4 inches in front of the 12th fret, just far enough away so that I won’t accidentally hit the mic with my fretting hand.
Compare the following two audio clips. The first clip was recorded using the cardioid pickup pattern, and the second clip was recorded using the omnidirectional pickup pattern.
In the second example (omni) you hear a little more room ambiance and reflection because sound is being picked up all around the mic, even behind it. In the first example (cardioid), you hear a little more pick attack and an overall brighter sound, because the strings and pick (in front of the mic) are more prevalent, with no sound being picked up from behind the mic.
In the next two examples, I have placed the mic directly in front of the sound hole. To reduce boominess, I have moved the mic back to about 8 inches away from the sound hole.
Again, the cardioid example has more pick attack and more brilliance, and also more bass, due to proximity effect, the bass boost that makes your voice so boomy when you put your lips right up to a cardioid vocal mic like an SM58. The omni example has a little less bass, because the omni pattern does not have proximity effect. I usually avoid the sound hole for fear of too much bass, but in this case I like the sound of the cardioid pattern here (although in a mix I might have to roll off some bass to make it sit well in the track).
MAKE ROOM FOR ROOM
You might think that only expensive recording studios have nice sounding rooms, and that your room must not sound very good, so you’ll just use a reverb plug-in to simulate a nice sounding room. I would say that yes, you can still add a nice reverb later, but those early reflections in your real room are not easy to duplicate. While recording my examples with the close mic, I was also recording through a stereo pair of AKG C1000S small diaphragm condenser mics (in an XY pattern) several feet away from me. Listen to the cardioid sound hole example again:
Now then listen to the following clip, which is the same recording, but with the stereo pair mixed in:
Hear how much space and stereo content has been added? This was not done in an acoustically treated room. It was just recorded in a small, lively room in an apartment with hardwood (laminate) floors and bare walls. Later if I need to, I can blend in a larger reverb while retaining my real room reverb for the early reflections.
A SLICK TRICK
Finally, one cool thing to try (which I did not include an example for): Record the same guitar part twice on two separate tracks (with the mic that’s close to the guitar). Then pan one track all the way left, and the other all the way right!
Every guitar is different, as is every mic, every player, every song, and every room. I’ve given you a few things to try, but when you go to do it yourself, I encourage you to experiment and let your ears be your guide.