De-humidifying & proper humidity control https://youtu.be/7P8gGK4944A?t=14s
Humidity advises video http://youtu.be/-cmX9o-gf4k?t=14s
1)
You should have a hygrometer (a simple one like this:
(*do not leave this sensor inside the case, it should be outside in the room you keep the guitar)
http://www.stringsbymail.com/store/index.php?main_page=product_info&cPath=2_405&products_id=4956
and only if it is under 40% humidity place (generally in winter time) the simplest humidifier in the head of the guitar case re-filling it with water every 2 or 3 days.
2)
Here is the link for the humidifier:
http://www.stringsbymail.com/store/oasis-original-blue-currently-not-blue-soundhole-humidifier-1656.html
The difference between Classical and Flamenco guitars http://www.rdiaz.org/rd-art%207.html
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^Ex.1/ 00:14 solo 1
Ex.2/ 11:24 solo 2
Ex.3/ 01:01 topic
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Nice link by Taylor Guitars
https://www.taylorguitars.com/sites/default/files/10_SymptomsofaDryGuitar.pdf
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Control humidity levels
https://youtu.be/XKeV7iCQVlA?t=14s