Why do guitars go out of tune?

Ah, when I'd asked about sharp tunings, I hadn't realised that there was a page 2 in this thread, where the topic has already been discussed!
Thanks for answering the same question twice!

Another possible culprit when guitars go sharp when you aren't playing them is temperature.

I yesterday, I played my travel acoustic for a couple of hours, and while it was reasonably in tune throughout, I occassionally made those little adjustments you always do, to keep it totally right.

Then I put it down, totally in tune and warm to the touch, because I'd been holding it, basically hugging the thing all evening. It sat all night in an air conditioned bed room (with the strings contracting in the cool) and this morning it was a semitone sharp across all the strings.

If you keep it in tune as you play, you're tuning it while it's warm. When you put it down, it the room is cooler than you are...it cools.

Best,
Ande

Also if they are really old ( 2 months ? ) and are all rusty, they can be in tune with the tuners but just sound out of tune, that happened to me yesterday until I changed the strings.

it's a conspiracy by string makers to force your ear to improve when you notice this and try to tune your guitar.

Then there's the counter conspiracy by makers of electronic tuners to prevent this ploy from working. Instead of using your ear to tune the guitar, you let a device tell you when it's okay again.

My 2 cents.

:mrgreen: