How to Record the Acoustic Guitar
Recording acoustic instruments can be scary for beginners. In this day and age many people just plug in and play their instruments, electric guitars, basses and synths, never needing to record an instrument except the odd vocal track. True as it may be that we get better sounds out our guitar plug-ins and software synths with every update, we must not forget how to record a “proper” instrument, in the real world.
The acoustic guitar is a great example of a popular acoustic instrument that is impossible to regenerate in the computer. The depth and richness of the acoustic guitar can never be reproduced without having to physically record it. No plug-in is going to replace the acoustic guitar, so you better start figuring out a good way to start learning how to record it.
Luckily, the next few words will shine a little light on how you can start recording that precious acoustic instrument of yours.
1. The Instrument
The acoustic guitar is a full-bodied and rich instrument. It has a wide frequency range consisting of thick lows and brilliant highs.
When recording we need to keep in mind how we are going to capture the full essence of the acoustic guitar with the resources we have available. It goes without saying, although the following sentence is going to say it, that you need to have a well prepared and good sounding instrument if you want a good sounding recording. You can't fix a badly set up guitar that has old and worn strings in the mix.
So before you start any recording tricks, be sure that the instrument is well set up, the strings are fairly new (restrung is better) and that it is in tune.
I change my strings every three months or so, and I recommend you restring your instrument as soon as you feel the sound losing its touch or feel the strings getting worn.
2. The Body
The body of the acoustic guitar is filled with deep lows, and when recording we need to not only focus on the energy that's coming out of the sound hole, but also other frequency information present in other parts of the guitar.
The strings provide brilliance and rich highs to your guitar sound. As said before, if you have worn out strings, you'll get a worn out and dull sound. So if you want a full bodied sound that's also rich in high end information you better make sure those strings sound good.
3. The Room (In Most Cases Your Room)
Where are you going to record your acoustic guitar?
If you have a really nice recording studio then you'll probably just opt for that nice sounding room that you use all the time to great effect. If you are a budding singer/songwriter that's much better with words and chords than recording interfaces chances are you have your bedroom to record in.
Be aware that your surroundings influence the sound of your guitar. You can find a nice spot in your room that your guitar sounds nice in, try recording in the bathroom for a livelier sound or put up blankets around you to deaden the reflections of your less than ideal recording space.
4. Where to Point Your Mic
Point and shoot! Get that acoustic guitar into your mic!
Actually, there's a lot more to it than that, as I pointed out in my last Basix tutorial Making Your Microphone Placement Work. But where to point and shoot?
Since the acoustic guitar has such a vivid and full range sound, there are parts of the acoustic guitar that accent some frequency ranges more than others. In the picture below you can see the different areas of the acoustic guitar and what you can hope to capture if you try to position a microphone there.
It is a common misunderstanding of beginners that the sound hole produces the best results when recording. By placing a microphone near the sound hole you can expect a very bassy sound since the resonance of the body has a very bassy sound in itself.
A microphone by the bridge can pick up a thick mid-range sound from the body of the acoustic guitar, but pointing the microphone at the bridge will also capture some of the string sound.
Positioning a microphone behind the acoustic guitar on axis with the body will capture the deepest low-end information from the instrument. If you try this method out be sure to flip the phase of the microphone if you are using another mic on the other side.
The area by the 12th fret is the sweet spot. This is where the neck joins the body and is usually regarded as the best place to record the acoustic since it is where we capture a full and even frequency response from the instrument. Not too bassy and not too brilliant.
If you need some extra string sound you could place a mic at the first fret to capture the nuances of the strings.
5. Which Microphone to Use
Due to the nature of the acoustic guitar, the narrow frequency range of the dynamic microphone is not that suitable to capture the full frequency range, highs, lows, bells, whistles 'n' all. The condenser is a much better bet if you want to hear the super awesomeness of a great sounding acoustic guitar.
The condenser captures all the information that the acoustic guitar has to offer and is a better choice over the ribbon microphone as well due to the ribbon's slower transient response if you are playing fast and strummy guitar parts. Besides, if you are just starting out, chances are you won't spend the money on a ribbon mic just yet.
As for the size of the condenser, a large or small diaphragm condenser work well. It's just a matter of taste and choice. A large diaphragm microphone tends to have a fuller sound in the low end while a small diaphragm condenser often has a high frequency boost.
6. A Few Microphone Techniques
Now that you have a better idea of where you can get your desired sound from your acoustic and have the microphone of choice in your hand, you are ready to record. But should you be using a single mic technique, combine a few different mic distances or get familiar with stereo recording?
A really good, foolproof idea is to start at the sweet spot. By placing a nice condenser at the 12th fret you are immediately closer to a great acoustic guitar sound. Now you can analyze what you think is lacking. If you want more lows you can either try positioning the sweet spot mic a bit closer to the sound hole, or you can place a second mic pointing at the sound hole or positioned by the back of the body.
For a more intimate strum sound you can place a second mic by the first fret, or you can mix a first fret mic with a condenser pointing at the bridge, picking up the thick mid-range of the body. Lastly, try experimenting with how close you mic up the guitar. A microphone capturing the full frequency of the acoustic at a distance can sound great combined with a close mic, especially in a sparse mix where the sound of the guitar will be dominant. Like I said before, check out the microphone placement guide for an in-depth look at the different microphone distances.
One of the most common and easy to use stereo microphone techniques for recording the acoustic guitar is the X/Y configuration. By placing 2 condensers in a 90° angle against each other you get a great stereo image with no phase issues. By pointing this simple stereo technique at the sweet spot on the 12th fret you can get an simple and easy stereo sound.
These are just a few of the basic recording techniques and plenty to get you started with recording your acoustic guitar.
I'll leave you to it. Grab a condenser and start laying down some acoustic guitar tracks. Record that country pop song you have in your head or fill up your rock track with some clean acoustic guitar tracks mixed in the background.
The acoustic guitar is a versatile instrument to use in your productions and shouldn't only be used for folk or country genres. The combination of some thick strings and a great sounding full bodied acoustic guitar can lend itself greatly to any production.
I sometimes even use it instead of my electric guitar, breaking my own rule I mentioned in the first paragraph plugging it into an amp simulator for a different sound. But like I've said oh so many times, experimentation is key to finding the perfect sound for you.