I just recently bought a classical guitar and it tunes perfect but goes out within 20-30 mins of playing, Is this normal for a new classical? also is there any type of "special" maintanence type things that classical's need done to them to keep them playing smooth and new?. Ty.
Are the strings new? Unlike metal strings, nylons need about a week to get stable. And no, I can't think of any special maintanence for a classical, it actually requires less because you don't have to wipe down the nylon strings (do wipe down the bass strings though).

Make sure your strings are installed the right way, otherwise they go out of tune.

Once the strings are properly installed and have had a week to set in, tuning is rarely needed.
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Thanks for that the strings have that crispy newness to them and rather flawless so im guessing there brand new as i bought it. As for the strings being installed the right way it looks like it is...ive never restrung an acousitc or classical yet =S (im dredding it lol.)
I had the same problem with my classical the first time I changed the strings; all of the strings are relatively in tune except for the D, which I didn't tie properly. I haven't been bothered to fix it yet, but I'm sure that's the problem...what may be happeing is that if the strings aren't tied properly, they're 'slipping,' which causes them to go flat. You can probably find some decent pics online (the guitar for dummies book has some good references too) on how to do it right...takes some practise, but it's not hard once you get it down.
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