Required equipment

• 1-4 microphones (dynamic, condenser, or ribbon) and mic stands (boom stands preferred)
• Something to record to (DAW, 4-track, etc.)

Optional equipment

• Mic Preamp
• Mixing board
• EQ, compressor, and harmonic exciter (outboard gear is preferred, plug-ins work well too)

Small cardoid condenser mics are preferred, but are much more revealing and hence, more unforgiving. You'll get a better frequency response, but it will tend to pick up more of what's in the room, including rustling clothes, breathing, squeaky chairs, etc. Do everything possible to cut down on background noise and electrical hum. Large cardoid condenser mics can work well too, but will pick up a lot more incidental and room sound than the small cardoid will.

If it were a perfect world, we'd all have loads of high-quality studio gear and a personal sound engineer to help us get the ultimate tone. However, we have to work with what we've got. A mic preamp is a nice thing to have, it can do a lot to color the signal and give it some depth. A mixer will allow you to easily hook up multiple mics and perhaps run a patch to some outboard gear. If you're going to use plug-ins instead, use good quality ones.

Don't be intimidated if all you've got is one microphone and a four track. With careful placement and room setup you can still get good sound. Dynamic mics can work very well, preferably instrument mics as opposed to vocal mics. The $90 Shure SM57 is still used as the go-to instrument mic by many professional engineers who have thousand-dollar-plus mics at their disposal.

Mic Placement, Setup, and Theory
The first thing you want to do is to figure out exactly where your guitar projects good sound. Get someone else to play the guitar and sit on the floor in front of it. You will be listening for "sweet" spots; there are places where the guitar will sound wonderful and places where it just won't. Keep in mind that because of the way your ears are placed on your head, what you hear is exactly what an ORTF position will deliver (see below). To get an idea of how one mic will sound, try plugging one ear and listening with the other. Even better: Monitor the mic with a set of closed headphones and move the mic around to find the best placement. Of course, sweet spots with one microphone will be different than sweet spots with two microphones.

These next two points are the most important parts of this lesson. On a higher level, understanding them thoroughly will make everything else in the lesson make perfect sense and will allow you to intuitively position mics to get the sound that you want.

• The further up the neck you go, the brighter the sound gets. You'll hear more finger squeak and fret sound and less pick sound. Conversely, the closer to the soundhole you get, the bassier the sound gets. You'll have more mids and lows and the sound will be a lot fuller. Positioning the mic at the tail of the guitar will give a bright but airier sound. You'll hear more pick and less finger and fret sound.
• On another plane, the further you move the mic from the strings, the more room ambience (reverb) the mic will pick up, and (when using two mics) the more mono the signal will become. Conversely, the closer you move the mic to the strings, the less room ambience the mic will pick up, and (when using two mics) the stereo separation will widen.

With all that in mind, the sweet spot (or spots) are somewhere in the middle. If you're working in a DAW, you can use spectrum analysis software to find a good balance of frequencies. You want fewer lows and mids when the guitar accompanies a bass and/or drums, and more lows and mids when the guitar is accompanied only by voice. It's bad practice to record the guitar with an untested placement and think that you can just clean it up later with EQ. You want the signal to sound as good as possible before it gets put to tape.

Setting up the room to record involves going into lots of detail that we won't go into here. That's another lesson for another time. But here's some quick thoughts on the subject: A typical room is a cube that has six sides or reflective surfaces. You want four or five those to be dampened so they don't reflect sound. You don't usually don't want a reflective surface to be behind you, and you don't want two reflective surfaces to be facing each other. If all surfaces are dampened, then the room is sonically "dead," and you may want to set up some sort of reflective surface in front of you. However, you usually don't want to be too close to a reflective surface, as some phasing issues can occur. As usual, experiment.

How you will go about setting up your mics depends entirely on how many mics you have and how many tracks you can record at once. Again, with careful setup, one mic can sound great, but having two mics opens up lots of possibilities. Most importantly, it will allow the recorded signal to come alive and give it a stereo image. Although it's preferred, you don't even have to record both mics to their own track; if necessary you can run both mics into a mixer and combine the two channels to one stereo signal.

A general rule when using more than one mic is to use the 3:1 method to avoid phase cancellation. That rule that states that the distance between any two mic capsules (or mic heads) should be at least three times the distance they are from the source. For example, if we have two mics and we place them 7" away from the guitar, they should be at least 21" away from each other. However, there are several exceptions to this rule, we'll discuss that below. Incidentally, being out of phase is not necessarily a bad thing. It's all a matter of personal preference.

One Microphone

Start by pointing it right at the 12th fret (or where the body meets the neck), spot-on and straight up, perpendicular to the fretboard. Keep it as close to the strings as you can and still play comfortably (3"-10" away). Don't point it directly at the soundhole, you'll boom the mids and lows badly. There will be some play; to experiment with different positions, imagine a 10" string attaching the capsule of the mic to the twelfth fret. You can move the mic around most of this range of motion quite a bit (keeping it pointed at the twelfth fret) and get different results. Remember, pointing it more towards the body gives a bassier, warmer sound and pointing it more toward the neck gives a brighter, janglier sound. Depending on your strings, playing style, how your guitar projects, and your personal taste, the sweet spot will be in a different place unique to each guitar and player.

XY (Coincident pair)

It's more than just the male chromosome. XY is a very popular and easy micing method that's used for guitars, drums, other stringed instruments, choral singing, etc. Cross two mics at a 90°-120° angle, and position them where one capsule is right on top of the other, almost touching (about a half-inch apart). This position produces a smooth and very natural sound, and consistently gives good results, but does not provide the widest stereo image. Phasing is not an issue. The 3:1 rule does not apply here; because any signal will hit the microphones at the same time. Start with this position around 5"-12" perpendicular from the fretboard and experiment in all directions from there.

ORTF

This standard was developed by the Office de Radiodiffusion-Television Francaise. The French Radio and Television Ministry. It is unique in that emulates the position of human ears and how they interpret sounds. The mic capsules are positioned 17cm (roughly 6.75") apart, at an angle of 110°. Get these measurements as perfect as you can for best results. Although not quite as smooth and foolproof as XY, many pros use this technique because it provides natural stereo spread and tonal qualities that the XY position doesn't. The 3:1 rule does not apply, not only because the mics are positioned away from each other, but because (in theory) the slight phasing that occurs will be accepted and interpreted by our brains as natural and pleasing. Start with this position about 8"-20" perpendicular from the fretboard and experiment in all directions from there. It is important to keep the capsules equidistant from the strings.

There are many variations on ORTF that you may wish to try. Here are a few:

• DIN, 90° angle, capsules 20cm apart.
• NOS, 90° angle, capsules 30cm apart.
• RAI, 110° angle, capsules 21cm apart.
• Olson, 135° angle, capsules 20cm apart.

Spaced Pair

Another widely used and popular technique. As XY, ORTF and it's variations emulate the ear, they are more suited for using two identical mics. But if you have two unmatched microphones, than the Spaced Pair method and it's variations will be what you'll want to use. Start with one mic pointed at the bridge and one mic pointed at the twelfth fret. The slightest change in how the mics are positioned can make a significant difference, so experiment a lot and see what you can come up with. If your mics are unmatched, try them in both positions the see what gives better results. Because of the 3:1 rule, it's difficult to place the mics more than 5" from the strings, and as always, it's important to keep the capsules equidistant from the strings.

Shoulder Float

This method does exactly what the name implies. The first mic is positioned perpendicular from the twelfth fret, but the second hangs over your shoulder and points down toward the bridge (the picture does not accurately reflect the angle of the shoulder mic). You'll have to have a boom stand to be able to make this work. This is a variation of the spaced pair and gives a bit more room ambience and natural feel, as some engineers feel that the stereo spread in a spaced pair position can be too artificial sounding. Many guitarists prefer this sound because it sounds a bit more like what we're used to hearing. Again, if your mics are unmatched, try them in both positions to see what gives better results. The 3:1 rule will allow the mics to be positioned up to 7" or so from the strings, and as always, it's important to keep the capsules equidistant from the strings. Also, in this position, the shoulder mic has to be pretty close to you. Be careful not to accidentally bump it or breathe into it while you do your take.

Three Way Spread

Another spaced pair variation, this is something I experimented with and it's become my favorite. I really liked the intimate sound of finger squeak on the fretboard, but the twelfth fret position of the spaced pair setup never gave me enough of that quality. I also liked the sound of the pick hitting the strings, and the twang that bridge mic gave. After much trial and error, I arrived at this setup. In my opinion, it gives the complete and balanced sound of the guitar from a player's perspective. Yet again, if your mics are unmatched, try them in all three positions the see what gives the best results. This position is not without it's problems, however. It's much more difficult to keep the capsules equidistant from the strings in this position. The player really needs to concentrate on sitting still while playing or major phasing issues will occur. Because of the 3:1 rule, it's difficult to place the mics much more than 5" from the strings.

Advanced Mic Positions and Combinations

Many studios will do something similar to this. This would be called a NOS nearfield with an ORTF room setup. It will allow for full and true capture of the essence of the guitar and the room. The NOS pair at around 6" captures a good stereo image of the guitar's nearfield qualities, and the ORTF pair about 3' behind gives a nice room feel to the mix. Use these kind of combinations only if you have a good and very quiet room to work in. Why do these mics appear to be positioned off-center? They aren't off center because the "center" for each pair is different. Because it captures the nearfield sounds, the sound source for the NOS pair is the strings. And because it captures room ambience, the (primary) sound source for the ORTF pair is the soundhole of the guitar.

Effects
As stated before, if it's a guitar instrumental or guitar-and-vocal only song, keep plenty of lows and midrange frequencies for a fuller sound. If the guitar is accompanying other instruments (drums or bass), it is very important to cut back the lows and mids significantly, as there will be plenty of instruments that need to occupy those frequencies. This is hopefully accomplished by adjusting the microphone(s) to give the correct amount of bass, treble, and reverb using the theory outlined in the Mic Placement and Theory section above.

As mic position is everything when it comes to what frequencies are present in the signal, the only suggested EQ curve I can offer is my personal preference that assumes a standard dreadnought guitar was miced with a dynamic instrument mic from 6" directly perpendicular to the twelfth fret in a dead room. It is recommended to approximate these settings as much as possible on a mixing board before the signal reaches tape.

• -1 to +3db @ 300hz (depends on accompaniment or guitar-only)
• -4 @ 1kHz
• +5 @ 4.5 kHz
• +3@10kHz

Use compression very sparingly, roughly a 3:1 ratio with a high threshold to pull down any peaks or spikes. Remember that too much compression will kill the dynamics of the track. Turn the threshold down in proportion to how "busy" the final song is going to be, i.e., how much other instrumentation is going on and how much it will have to fight for it's sonic space.

Like compression, harmonic exciters like a BBE Sonic Maximizer or an Aphex Aural Exciter are a good thing to add in moderation. Remember that they are generally used to compensate for bad speakers and to make your mix travel well. Try it first with the settings low, and test on another output source than your monitors. Don't get too eager with this device, it can easily add too much of a glossy sheen to the signal and make it sound artificial. Your ears should be able to tell you when to stop.

Conclusion
With a little theory on mic placement and the guitar's soundfield, you should be able to approximate the sound you want even with minimal gear. You should have the information you now need to be able to record successfully. Some things not covered in this lesson that are worth additional study are:

• Room setup
• Mic baffling
• General recording techniques

Thanks for reading. Remember, if there are any questions or any clarification needed, just post up a question over in the "PC Recording" forum. We'll get it sorted out.

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