How to use an electric tuner for an acoustic guitar?

Most electronic tuners have a built in microphone to allow you to tune acoustic instruments. Set the tuner for guitar of chromatic and pluck the low E string. Typically a needle will show you weather you are flat (too low) or sharp (too high) If it is right in the middle you are in tune. Most modern tuners will automatically sense what string you are playing when you pluck it UNLESS you are WAY out of tune! If this is the case I would recommend taking the guitar to your local music store and let them tune it for you and show you exactly how to use the tuner. Once you have it done for you once you should be able to do it yourself. Be sure to thoroughly read the instructions of the tuner to understand its features and how to correctly use it.

That's the wrong tuner for an acoustic guitar. You want a clip-on like the Snark SN-5 or the IntelliTouch. You simply clip it to the headstock and tune each string one at a time until they're all in tune. http://www.zzounds.com/item--SNASN5

You shouldn't need to calibrate it. It should already be set to A = 440. If you know that it's not, you need to look at the instructions and at the tuner itself to see how to calibrate it.

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