If you record acoustic guitar, then chances are you’ve either played around with stereo recording or at least thought about it. But maybe you’re not sure which techniques to use and the pros and cons of each.

I think I can help.

I’ve recorded acoustic guitar more than any other instrument, so I’ve spent countless hours of quality time with my guitar and a pair of microphones. And I’ve gotten pretty good at getting great acoustic guitar tone.

What is stereo recording?

Stereo recording is simply using two microphones to capture a two-channel “stereo” image of the source. By panning the signals left and right, you can create a sense of space and width and depth, simply by using two microphones instead of one.

Stereo mic techniques can be applied to any acoustic instrument – drum overheads, piano, cello, upright bass, choirs. I’ve used these same stereo techniques on all these instruments. So even if you don’t record acoustic guitar, keep reading. These techniques apply to all kinds of recording situations, and it’s good to be familiar with them.

Mono recording (using only one microphone) is still very useful. There are plenty of times where I’ll simply use one microphone on acoustic guitar, especially if it’s for a bigger production where the guitar is playing a minor role. If the guitar is a big focus of the song, then I’ll probably stereo-mic it.

Check out these two articles for more on stereo vs. mono recording:

Here are 5 stereo-mic techniques I use fairly regularly. All but #4 can be applied to almost any instrument.

1. XY

XY is oftentimes my go-to stereo technique. Why? Because it doesn’t lend itself to phase issues. Phase issues can occur when multiple microphones pick up the same source. If the microphones are in different locations, then there’s a chance they’ll pick up the sound at different times.

Imagine taking two identical tracks in your DAW and delaying one by a few milliseconds. (Go try it if you’ve never done it.) What happens? Things start sounding thin. That’s what happens when your two mics are out of phse.

With the XY technique, the mics are essentially at the same point in time, so any signal will hit both microphones at roughly the same time. It essentially gets rid of phase issues.

Pros – stereo image without any phase issues

Cons – not as “wide” of an image as other techniques

2. ORTF

ORTF (it stands for some French phrase) is essentially taking the XY technique and flipping them outwards instead of inwards. The idea here is to create a recording that sounds very close to how the human ears hear.

The mics are approximately at the same distance and angle as our ears. On headphones, this technique sounds incredible. It’s as if you’re sitting in front of the guitar listening yourself. (For specific specs on ORTF, click here.)

Pros – realistic stereo field

Cons – some potential phase issues

3. Spaced Pair

Spaced pair is just like it sounds. You set up two microphones spaced out, facing the instrument. Spaced pair is the most susceptible to phase issues. I almost never get it right the first time. It requires a lot of attention and listening to get it right.

Spaced pair can give you a huge, wide sound, but only if you get the two mics in phase. The way I normally go about making sure they’re in phase is to listen to the mics in mono. I’ll pan both tracks to the center, and move the mics around until the mono signal sounds nice and full. If the sound is missing a lot of bass and sounds phasey, I know the mics aren’t in phase yet.

Oftentimes just moving one mic a few inches will fix the problem. Once the mono signal sounds full and huge, you’re ready. The stereo signal will be enormous. Be careful, though. If the guitarist moves or rotates a bit, you might be back out of phase again.

Pros – very wide sound

Cons – very susceptible to phase issues, “center” isn’t as clear

4. Over-the-Shoulder

Over-the-shoulder is a technique I’ve only used occasionally. Essentially you put a mono mic in front of the guitar and another mic over the neck pointing down. While this isn’t a “true” stereo technique, a lot of engineers use this as their default setup for recording acoustic guitar.

I find it to be a bit fickle. The front mic captures the body of the instrument, while the shoulder mic only captures the higher-end sound and pick noise. That means I can’t really pan these very wide without it sounding funny.

It can give an interesting stereo image with lots of fret noise, if that’s what the song needs.

Guitarists tend to like this technique because it sounds a lot like the guitar sounds to their ears when they’re playing it.

Pros – if shoulder mic doesn’t work, you can still use the front mic as a mono mic; grabs more finger/fret noise and “air”

Cons – not really a L/R stereo technique, tends to capture a lot of pick noise, phase issues are still a concern

5. Mid-Side

Mid-side is the most complex technique, but it’s pretty cool. The setup is one cardioid (or omni) microphone pointed at the guitar and another figure-8 microphone facing perpendicular to the first mic.

The mid mic gets recorded to its own track. The side mic gets recorded to TWO separate mono tracks (record the same signal to two tracks), panned left and right. Flip the phase on one of the tracks.

This allows you to adjust the width of the recording. The more you bring up the side tracks, the wider the sound. The more you bring up the mid mic, the more “mono” the sound. What’s great about this is you can change the width after-the-fact. If you’re mixing and wish the track was wider, you can make it happen. You can’t do that with any other technique.

Like the XY technique, mid-side doesn’t tend to have many phase issues, because the mic capsules are so close together. If your room is noisy or not very well treated acoustically, then this technique might not be for you, as the sid mic is picking up everything to the left and right of the guitar (your room).

Pros – very little phase issues, mono-compatible, adjustable width

Cons – more complex/confusing to set up, having too many choices may bog you down later, harder to ‘commit’ to a sound

If you want to learn more…

The images in today’s post are straight from the content within my Recording Acoustic Guitar course. If you’re interested in learning everything there is to know about recording an acoustic guitar (both in mono and stereo), then check it out. You’ll learn how I record acoustic guitar, and you’ll get to hear all these techniques in action. It’s a LOT of fun. Click here to check it out.

Comment Time

Do you use any of these techniques? There are plenty more stereo techniques, but these are the five I like to use. Which ones do you like? Which ones are you going to try next? Leave a comment and let us know!

  • Jim

    Check out the book by Bruce Bartlett “On Location Recording Techniques”. It’s the bible of stereo recording with plenty of diagrams and common sense explanations. $10 on Amazon. It’s a book you’ll keep forever.

  • Jim

    Speaking to the “fake” M/S recording, there is a way to do that. Take two pencil cardioid mics and point them 180-degrees away from each other (tail to tail, if you will) left to right and invert the phase on one of them. Place a cardioid facing front between them along the same axis. Adjust the width of your stereo field the same as you would a normal M/S setup.

  • Jasper

    I really like the mid-side set up and the variable width possibilities of it later on. That said, I don’t currently have a mic for side (no figure 8 mic), which hopefully I’ll solve soon. That said, is there not any reason that one couldn’t do a, sort of, ‘mid-xy?’ I just recorded a bit that way for a project that isn’t of the highest importance (an album is coming up, and I’m pretty set on mid-side with a proper side mic – thinking a K2, used for vox, also), and really it’s not too bad. The two cardioid pencil mics that I have are not great quality, so that leaves some noise and a bit to be desired, but that’s always the case. Otherwise, it seems to have had perfectly fine results. An odd thing that I haven’t figured out if I possibly like is reversing the phase of the xy mic facing toward the neck of the guitar. Obviously, for standard xy, this would be a terrible idea, but since I’m combining it with the mid channel as the main, it gives an interesting calmer width to it, though I do fear it may be a situation of ‘sounds cool for a short time, then fatiguing.’ Aside from that aspect, ‘mid-xy’ does seem to work.

    • You’re asking interesting questions, but when the questions get this technical I’ve found that we start to miss the point. I don’t think it’s possible to fake a mid-side recording without a figure-8 mic. But I also almost never record acoustic guitars in stereo anymore, and I’m happy with that too. 🙂

  • Dan Contento

    Can you offer any technique to properly mic-up a nylon-string, Spanish style acoustic guitar that will be finger picked?

    • Honestly, I’d approach it like anything else. Pick a spot, place the mic, see how it sounds, then repeat.

  • John Lawton

    Interesting article, tho’ the popular but incorrect misusage of ‘issues’ when you mean ‘problems’ is annoying.
    ORTF is Office de Radiodiffusion Francaise, French which–loosely translated (I’ve never studied French, but, there’s some English hidden in there) means: The French Office of Radio Transmission. The USA equivalent would probably be the FCC, the Federal Communications Commission. The ‘hidden’ English is ‘diffusion’ meaning to cause to spread out broadly. In English, we normally say “to broadcast” which means to “transmit widely”.
    Never doubt the power of the proper usage of English vocabulary, grammar, and punctuation to effectively get your message across. Don’t be a Microsoft drone (they may not have started it, but, they widely spread the misuse of ‘issue’ instead of ‘problem’, probably because they don’t have to fix ‘issues’, but, they’ll talk to you about it over the phone for a steep fee): use ‘problem’ when you mean a situation needing adjustment, rectification, modifications–needing some type of action–for someone’s or something’s benefit; use ‘issue’ when you mean a topic for discussion. While there is almost always an issue associated with a problem, the two terms are not identical.
    😀

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  • Zach

    Just used the “Over the Shoulder” and my client and I loved the sound. We were recording a mid-to-high-end Taylor Acoustic. I noticed in your photo that you are micing over the shoulder near the neck of the guitar. Have you tried micing over the body side? If each mic is equidistant from the soundhole you shouldn’t have much in the way of phase problems.

    • I’ve played with over-the-shoulder a few different ways. Just never liked it all that much personally. Glad it worked well for you! 🙂

  • Dave

    Joe, does photo #5 really display the following description?

    Mid-side is the most complex technique, but it’s pretty cool. The setup is one cardioid (or omni) microphone pointed at the guitar and another figure-8 microphone facing perpendicular to the first mic.

    These mics don’t appear to be perpendicular to each other. I assume the Earthworks is the omni so maybe if it is conceived as a circular pattern (omni) then the Earthworks would HAVE to be perpendicular to the figure 8 mic? (but where is the placement of the guitar?)

    I have tried mid-size many times with no luck, so that is why I inquire.

    • Hey Dave. They look perpendicular to me. The Earthworks mic is pointing forward, towards the guitar. The other mic is “facing” sideways.

      • Dave

        Got it. I couldn’t tell where the guitar was positioned. Dave

  • Rick Hirsch

    Timeless, good basic info in this article and a must read for any audio engineer. Thank you.

  • Judex

    Very useful tips indeed.

    I am an adult learner. I now realize that I was trying hard with my violin, and was never satisfied. I had to move to another room to get better sounds. Still, I need to prepare a room where I could practice.

    Thanks a lot.

  • Lucius

    I’ve been experimenting recently with drums and find MS entering more and more of my sessions. Blumlein technique can also achieve some wicked drum room tones, but XY is pretty fail-safe and fairly wide. If you’ve a room you like, Blumlein could yield impressive results for an acoustic guitar.
    Grab some R40’s, and some Lundhal OP transformers! It’s worth it.
    I haven’t tried out ORTF or the other “ears” techniques on anything really..:(
    The experiments continue!

  • Joseph Lyons

    Just a quick question Joe. What kind of mics are these? They look like Earthworks M30s…I could be wrong bc I’m not a mic guru, but if they are aren’t those omni mics? The only reason why I ask is because a lot of people tell me not to use xy config with omni mics…whats your stance on it?

  • On a side note, nice to see Earthworks mics represented. Very transparent mics!

  • Great article, Joe. I second Mr. Bauserman’s comment, it’s good to see a lineup and comparison.

    I tend to lean toward ORTF myself – such a wide image. And if it’s not enough, you can stick some foam between the mics to widen it even more.

    I’ve been wanting to try the M-S configuration. Technically the wideness of any method adjustable with Panning, but this one is the easiest since the wideness is defined by one track, not two (one stereo fader if you use the three-channel method).

    • Andrew Bauserman

      M-S wideness is very adjustable, if you have a treated room. The side mic has its dead spot toward the source. Great for adding width, but only if it’s worth adding.

    • Thanks dude. Cool tip on using foam to make ORTF wider.

      You’re right that you can adjust wideness with panning, but all my “wideness” comments in the article are based on the tracks already being panned hard left and right. Some techniques lend themselves to a wider sound than others, regardless of panning.

  • I use a rather odd two mic technique. I have a large diaphragm condensor set slightly above the sound hole, capturing the guitar, and possibly vocals if I’m in the mood. The second mic is a pencil condensor pointed at the 12th fret. I primarily use the LD mic in the mix, but bring in the pencil for color. I haven’t noticed any phase issues, but I’ve also never checked, so I may be missing something.

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  • Al

    Very informative post; I’ll take it as christmass giveaway.
    Thanks Joe.

  • Chawps

    I’m usually a spaced-pair kind of guy, but your descriptions of XY and especially ORTF make me curious to branch out a bit. Thanks for the article!

  • Raphael Cassis

    great article! I’m running a project that the guitar is the main instrument so I would like to have it stereo… So there is a big problem, I don’t have stereo mics… the only thing I have is a large diafragm condenser and two dynamics standards, but different from each other… What do you advice me to do? Thanks
    PS.: Doesn´t worth a advice to buy a new mic… 🙂

    • Brett

      What worked for me in this situation is to place one of the dynamic mics close to the bridge of the guitar, one dynamic pointed towards the 12th fret, then use the condenser as a room mic to capture the space.

  • M/S stereo techniques; as Joe says, you can record to three tracks or you can record to two (M & S) and when mixing, the side signal is split to feed two channels, one channel with polarity reversed (NOT phase!) This gives you a cheap and simple matrix decoder.

    If you want to vary the stereo width, you can always vary the pan of the two S channels.

    However, if you are going for this technique, I would recommend a Figure 8 mic with a good polar response and not be too ‘cheap and cheerful’ 🙂

    • JonnyNinja

      Terry, what do you think about the following?

      I don’t have a bidirectional mic, but I’ve been recording acoustic with a spaced pair. I’ve been experimenting with duplicating one of the channels, panning the duplicates hard left and hard right, and inverting the phase on one of them. The other original track (the non-duplicated one) stays panned center. It sounds mono compatible when I check it (the sides cancel out, leaving the center intact). Based on the mics I’m using (km184 and TLM103), I seem to prefer this sound as opposed to panning just the two tracks apart from one another or stacking and blending them. It just sounds “bigger” and more pronounced to me.

      Apart from the fact that I don’t get all that room tone from a bidirectional mic, do you see anything technically wrong about this?

      It seems that in my head it checks out, and I don’t sense any phase issues with my ears (I also observe the 3:1 rule when recording them and check that they’re in phase on the waveform and with my ears when stacking them in mono).

      Assuming this does pass the technical sniff test, would there be anything wrong with putting the mics closer together (as opposed to a spaced pair) and implementing the technique described before?

      I’m just looking for someone to poke some holes in what I’m doing as a third party gut check.

  • ORTF was the old name for French radio & television. They did (and still do) a lot of research on microphone techniques.

  • Bob Sorace

    I’ve only used the spaced pair, or just one mic pointed at the 12th fret if I’m being lazy. I haven’t recorded a lot of acoustic lately, but my results were always hit or miss, but I’m looking forward to trying some of these out though!

  • Again, another great article. Thanks Joe.

  • Noah

    Joe, great post. On mid side, do u know how it would sound to just use two tracks? pan the mid far left and the side far right? (i dont have a figure 8 or I would try it myself).

    • Jim

      Mid-side takes three tracks because the side- mic is a figure 8 covering the left and right sides. You need two tracks for this to be able to switch the phase of one of them. Then the mid-mic needs to be in a separate track.

      • John Bercik

        you can use Voxengo msed vst with mid in left and side in right to a single stereo track. Set it to decode and adjust side to -12db to start.

  • I’ve never done M-S because i always thought you had to have a certain type of box to process them. (Something about a “matrix”?) Never knew you could just do it manually. Thanks. Now i need a decent cheap fig-8 mic!

    • Xan

      Maybe you could try simulating the fig 8 mic with a couple ov cardioids pointing in opposite directions. It might work or it might even have a new sound altogether..! 😉

      However I would suspect that if this was done and each was recorded on a separate channel the phase reverse would not have to be done as each mic capsule would already be pointing in opposite directions, so they would essentially be already in 180 degree phase-shift.

      • Andrew Bauserman

        Most Figure-8 are tighter than cardioid. Use super-/hyper-cardioids if you can. Flip the phase on one, because it’s not just
        Left = mid + left-side
        but actually:
        Left = mid + left-side – right-side
        This subtracts right-side bleed from the mid to widen the Left signal. Likewise subtracting left bleed widens the Right side. If that makes sense…

      • Sounds like it would be in interesting experiment. The two signals would have to be summed together as a single mono signal and THEN used in an M/S matrix or like I described above, but would possibly be interesting. You should try it!

  • What about the 3 to 1 rule and with the xy technic one mic should be over the other so they’re not pointing in each others way i believe? The pic doesn’t show this very well. : )

    steve

  • César

    What about the NOS Technique? It´s quite similar to the ORTF but I think is a little bit more realistic

  • Sad Panda

    I always do XY. It’s easy, it sounds great, there’s still some stereo to it, and it’s really hard to muck up the setup. ORTF looks like it might be very similar but with a wider image, so I’ll have to check it out. Plus it appears I can use my stereo bar and small-diaphragm condensers that I already have. Something nice and new to up my arsenal of tricks.

  • I’ve always been confused with the mid-side setup. The picture says it all. Thanks for this post!

  • Andrew Bauserman

    Cool to see the stereo techniques all lined up on one page 🙂
    I’ve used ORTF to record live drum overheads. More separation than X-Y; minimal phase problems. Recorder-man (equiv. to over-shoulder on acoustic?) is cool for tracking, but tough (for me & my drummers) to keep the distances lined up in a live gig.

  • I really like number 5! That’s an awesome idea!

    I’ve done 4 mics before. A bit overkill, but it was (1) piezo, (2) soundhole, (3) fingerboard, and (4) room mic. It’s similar to the spaced pair (#3). Eager to try the other ones you have!

    Thanks, Joe.

  • great article Joe!! I’ve often found myself torn between a couple of these configurations but the XY is what always seems to work the best. Keep the center image in check for me.