Recording techniques and strategies that keep the artist and the song in the foreground
By John McVey
Acoustic guitar is perhaps one of the most played, and as a result one of the most recorded, instruments today. Knowing how to get a good sound on an acoustic guitar is an important skill; as with anything, some of it is intuitive, but there are some definable guidelines that can be helpful.
As a producer/engineer who spends a good deal of time in the singer/songwriter world, I find that recording acoustic guitar is a huge part of what I do. I imagine it has been a central part of your music and recording as well; at the very least, few of us get away without recording one for very long! I get a lot of questions about how to do it well, and want to share some of my answers with you.
On Mics & Miking
Creating the environment
I will start where I always start, which is that recording anything is about the performance! A bad performance recorded well is still a bad performance. A great performance recorded badly is still a great performance. Naturally, capturing a great performance well is the ideal.
Setting up mics and designing your signal path is only part of it. Making sure the musician is taken care of is a larger part. So it is always my goal to provide an environment in which the musician can give his or her best performance.
I often start by getting to know them a bit. Have they recorded before? What kind of music do they play? What kind of music do they listen to? How long have they been playing? How much do they perform live? What are their goals for this recording project? This tells you a lot about what you’re about to do. It develops a relationship with the musician, and gives you lots of info about what they want to get from the session. Even if you already know the musician, or if it’s you, you should still start by talking or thinking through what you’re about to do. The same questions apply and the answers are still helpful.
Preparation
Before a session, I often have a pre-production conversation with the musician about what we’re going to do. A week or so before they come into the studio, we’ll talk a bit about what they’re recording. If the guitar (and/or a scratch vocal) is the first step in the process of recording a full band, and they’re going to be playing to a click, I have them get used to it by practicing with a metronome. This sounds really obvious, but it can be a bad thing to find out this is the first time they’ve ever played to a click, or to realize in the session that they can’t make the part feel natural to a click!
Practicing beforehand will make the session go more smoothly and produce a much better end result. If the musician is playing to a mix of other instruments, I’ll often make a mix for them to practice with, well beforehand. This too can make them feel more comfortable in the session. And I’ll answer questions about what they might expect in the session. All of this puts them at ease before they even walk in the door. And again, if it’s you doing the recording, practice with a click and preparation ahead of time will benefit you as well.
Here’s a typical mic positioning for capturing acoustic guitar.
Form follows function
It’s important to know what this particular guitar is going to be doing in this recording. Is it part of a 9-piece band, or is it a guitar-vocal piece, or solo guitar? Is it rock, bluegrass, classical, jazz, folk?
What is its function? If it’s a rhythm part for a rock song, it will have different needs than if it is a solo guitar piece or guitar/vocal, and I’ll choose my mic, preamp and compressor based on those needs. Later I’ll make EQ, panning and mixing choices as well based on this information. I will want to have done things right from the start, and I will want to have captured everything I might need later. A little talk about this before the session is essential.
Mic choices
First of all, does this need to be stereo or mono? I tend to begin with stereo, just in case the image might need to be spread out in the mix. And I can always pan the two mics together, or simply choose one of them later, if the mix calls for a mono sound.
My go-to setup is a pair of Coles 4038 ribbon mics. These are stunning—fat without being tubby, and very natural-sounding. My other go-to set is a pair of Royer R-122 active ribbons. These are also wonderful-sounding guitar mics.
While I like ribbon mics on acoustic guitar, I’ve used all kinds and still do, based on what the guitar is doing in the recording. Small-diaphragm condenser mics (like the Neumann KM 184) have a very bright sound, useful for big mixes or dark-sounding guitars. A large-diaphragm condenser can be a wonderful room mic, and omni mics are great for recording guitar and vocals at the same time without phase issues.
You may not have a lot of mic choices, and that’s okay! Even a Shure SM57 can be useful, and an unmatched pair of mics can yield very nice results too. Try to learn what each mic you have captures best. If you have a mic that tends to be bright, position it where this sound is most effective, or where a lot of low end is coming out. If you have mics that tend to be darker-sounding, position them where more high end is coming out.
An isolation device can help improve your sound in a difficult room.
Sweet spots
Mic positioning is vital when recording acoustic guitar, as with any other source. My favorite mic positioning for two mics on an acoustic is (1) just below the neck where it meets the body, 8–12 inches away, and (2) just below the bridge and a bit toward the strap peg 8–12 inches away. These are two very sweet spots for most guitars.
The first mic has many possible capture options. It can be moved or aimed toward the sound hole for a more full, even boomy sound, or straight at the guitar for a more bright sound. Those of my clients who have big guitars, or play with a lot of energy and volume, may need me to aim the mic away from the sound hole more. Others who play more softly, or who have a slightly fret-buzzy playing style, may require me to aim more away from the neck and toward the sound hole. I rarely put a mic right in front of the sound hole, unless the recording or playing style calls for a deep, bassy sound. And in these cases I’ll put it a bit farther away to allow for proximity effect.
In all cases, I have the musician play and get my ear in front of the guitar where the mics might be placed. Each player and each guitar are different, and by moving my ear around in these areas I will find where the sweet spots are for this particular player and instrument. I will choose mics and positioning based on what I hear. If it sounds right, it is right!
When placing a mic/mics, I will always be sure the player is comfortable and can stay in the same position until we get a good take. I will set levels, but will adjust them during the first run through, because musicians often play differently when the Record button gets pushed! And I’ll keep an eye on the player’s position in front of the mics to look for changes as we go along, as slight changes in position can lead to differences in sound between takes.
Close or far
Close miking yields a very detailed sound. Proximity effect (the increased bass when a directional mic is close to the source) is important to consider, and I will generally move the mics in closer and farther away to see what sounds best.
Your room is also a consideration here. Obviously, miking farther away captures more of the room. This can be good or bad, depending on how the room sounds and how the guitar is to fit into the mix.
Experimentation is key! A roomy sound can be great if the guitar needs to fit into a mix in which other instruments have some room in their sound, but this can also be achieved by using close miking and small room reverbs. With someone who plays very softly, a lot of string noise can be picked up that is as loud as the notes being played. It can be a delicate balance getting close enough to capture good, full sound, but far enough away (and with the right positioning) to capture more note than noise.
Click bleed
Often it’s important to turn up the click in the player’s headphones so they can hear it and play cleanly in time. When using a click, one of the first things I do—after getting a good sound and making sure the player is hearing what they need—is to record a bit of a scratch take, then solo the guitar mics and listen for click bleed.
I go to a place where the guitar isn’t playing and make sure nothing is bleeding through from the headphones. Nothing is more distressing than realizing, too late, that there’s click coming through the mics in that one quiet section, or in the final chord of the song as it fades out!
Doubling
This can be a great way to achieve a big fat guitar sound. It’s important to consider how the musician plays. Some folks aren’t particularly adept at playing the same thing twice. Small differences between takes in a doubling situation can be nice. But too much difference can ruin the effect and make it sound less like a double and more like a mess!
Check out how the musician is doing as you go into the doubling take. Often the musician relaxes, having already gotten a usable take in the can, and starts playing with a more easy feel… and suddenly the double becomes the main part!
The two takes can be panned wide, leaving room in the middle of the stereo field for other things. This can be really helpful when there are three instruments to balance. Putting two on one side of a mix can lean the whole thing to one side. However, if a doubled guitar is one of the three, and is spread out far left and right, the other two can be balanced on either side to great effect. This can also be nice in a guitar/vocal song, with the doubled guitars spread wide and the vocal in the center.
While recording the double, it can be wise to spread the two takes far right and left, and let the musician know which they are hearing where. This way, they can more easily match the takes. If this isn’t done, the musician can get confused and may not be able to match what he or she did the first take.
To compress or not to compress?
This will depend on the style of playing. If the guitarist is banging away at the guitar, less compression will be needed… or even wanted. If the playing is very soft, more compression may be needed—but be careful not to compress too much, as this will yield more noise than notes!
Always keep in mind that compression can be added after the fact. A bit of compression on the way in can be nice, especially if you have great compressors with a nice sound. But too much compression can be hard to deal with later. I have a colleague who likes to say that the Gain Reduction needle on the compressor should be like a “blade of grass in a light breeze!” It should just move down gently during louder parts, rather than slam down hard the whole way through. This yields a nice, full tone. Remember, though: more can always be added later, so never overdo it in the recording stage.
Playing styles and advice
There are times when it can be wise to advise a player on how they play a part, e.g. to play louder or to back off. If the player is playing so softly that the mics need to be turned up so loud that you hear them breathing as much as playing, ask if they can dig in a bit more or use a pick. Conversely, if they are playing so loud that the guitar’s tone is gone, it can be good to ask if they might play a bit more softly or try playing with fingers.
Volume does not necessarily translate to vibe or good sound in the song. I often find that precision playing is more effective than loud playing to add energy to a song! Having the player come into the control room and listen to an early take can be a great way to help them figure out what’s best. Always keep in mind who you’re talking to; some artists can be delicate around what they perceive as criticism of their style. It’s true that too little advice can give you fits when you get to mixdown and realize you don’t have exactly what the song called for… but too much advice can kill a session’s vibe fast!
Here’s a sample EQ curve for recording acoustic guitar. Note the gentle control of low mids and the drastic rolloff of extreme bass (which will only have thumps and mic rumble).
EQ after the fact
I’ve gotten more brave over the years about EQing on the way in. I now know a lot more about what I’ll want in the end, and I can take some frequencies out or turn them up a bit to help get closer to the sound I will ultimately want. But I’m always careful not to do too much, for fear I might find myself married to something that isn’t as satisfying when we get to the mix.
It never hurts to take lots of raw “sonic information” when recording, and worry about shaping it more later on. If you don’t have a ton of experience recording acoustic guitar, always err on the side of doing less to the signal as you capture it. It’s very hard to completely undo processing on a signal that was done as it was recorded.
The song will tell you what’s needed… listen to it! Some detailing of a recorded acoustic guitar can be a great thing. If the guitar is by itself, with only a vocal or perhaps a few soft instruments, you may want a more full and unprocessed sound. If the guitar is sitting in a big mix, more shaping may be necessary.
In a band situation, lots of instruments have low-end information in them. Vocals, basses, drums, almost all instruments recorded through microphones have low and/or low mid information that can build up in a mix and make it sound muddy. I find that pulling out some of this in a guitar can help it pop out in a mix in just the right way. I’ll often set a low shelf, or roll off everything below a certain frequency (like 80-100 Hz), because there’s information down there that conflicts with other instruments. Besides, in many songs, most of that boomy stuff doesn’t really make a guitar sound its best anyway. However, if it’s a solo guitar, I often leave this in (or move my shelf or rolloff lower, taking out less of these frequencies), so that the entire frequency range is represented.
A bit of really high end can help make a guitar sound detailed and beautiful. I’ll usually try to add some highs, particularly above 10 kHz. This can make picked guitars sound more percussive, and fingerstyle guitars sound sweeter. Just be careful not to add frequencies that bring out too much string buzz or fret noise.
In almost any guitar and player combo, there will be frequencies that aren’t particularly beautiful sounding, or that interfere with other sounds in the mix. I can usually hear that there’s something not right, so I’ll put up an EQ band with a very narrow Q, turn it up loud and sweep it back and forth in the area I think needs attention. Usually this will show me exactly where the problem is. Once I find it, I can take that frequency out to the degree that’s needed (a little can go a long way!) and adjust the Q wider if it sounds better. Again, experimentation is good thing here—setting EQ to extremes, then backing off once you’ve found problems to solve or nice-sounding areas to accentuate, can be very effective.
Recording yourself
For those of us who are both recordists and players, it can be very satisfying to set up a few mics close to your computer keyboard, so you can start and stop recording as you need to for that perfect comped-as-you-go take. This is only good for those of us who have a quiet control room environment, as there’s nothing worse than realizing at mix time that there’s computer fan noise in the background that gets really obvious at quieter spots in the music.
There are fancier solutions, like a silent workstation out in the tracking room, but sometimes all you need is a microphone isolator like the Aston Halo,Auralex MudGuard, Primacoustic VoxGuard, orsE Electronics Reflexion Filter. They can be really effective in places where there might be other noise happening. I’ve built these myself at times by shaping foam using a clothes hanger and some duct tape.
I hope some of this is helpful—now go make some cool guitar tracks!