As we know from our previous look at recording acoustic guitar, using a microphone gives you much more control over the guitar tone and a more natural sound than you would get through a built-in pickup. If you want something a little more advanced and a bit special for your guitar sound, then record it in stereo.
You might think a stereo technique for acoustic guitars is overkill since it’s such a small instrument compared to something like a grand piano which you would expect to record in stereo. So why isn’t a single mic enough?
Honestly, the best way to find out is to give it a go and hear the difference yourself. The ‘middle and side’ technique or ‘m/s’ is the perfect tool for the job, because it allows you to listen to the mono mic and then fade up the stereo. It will also give you a very natural sounding stereo image with minimal phase issues if you decide to make it quite narrow in the mix. It is slightly more fiddly to set up then just rigging two mics and panning them left and right, but it is a more versatile technique and can give really nice results.