I've had this guitar for a couple of years, and I'm now noticing that the notes are getting sharper as I go along the fretboard. The open strings will be perfectly in tune, then by the time I get to the twelfth fret it's quite sharp. What's the problem and how can I fix it?

Any help is appreciated!
that's your intonation - you'll have to adjust the position of the saddles (or the whole bridge if you've got a les paul junior style guitar, for example) with whatever adjustment screws are available and move the saddles downwards (further away from the nut) until it's accurate - you know it's accurate by comparing the 12th fret harmonic with the fretted note at the 12th fret on each string.

If you're not comfortable doing that yourself (although it's always helpful to learn) then take it to a guitar shop and they should do it for you - but it will cost you a little bit of money.
I like analogue Solid State amps that make no effort to be "tube-like", and I'm proud of it...

...A little too proud, to be honest.
Yep. It's intonation problem, alright. To save yourself and us sometime follow this link http://tinyurl.com/2etvhwf

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