Winter seems to be the toughest time for guitars, fiddles and other wood instruments. Outdoor cold temperatures, indoor sources of concentrated heat, and indoor low humidity are the main concerns.

Most brochures that come with new instruments will cover cold weather care. It is important to read the information to avoid any problems with your instrument.

Extreme cold temperatures are bad for an instrument, especially instant contact, such as when an instrument is taken outside without a case. Finish cracking is almost guaranteed, because when the finish meets the cold air it chills and shrinks faster than the wood underneath. (One customer told of pulling a guitar out of the case in the cold and seeing the cracks in the finish instantly appear all along the top, back and sides of the guitar.)

Indoor sources of heat such as radiators or heat vents can cause the finish to soften or glue seams to open. Space heaters can also cause scorching or melting of finish or plastic bindings and pickguards.

Low humidity is the most common problem. If your house is not humidified in the winter you should have a humidifier in your instrument or case. Low humidity is not as extreme a condition as those listed above, but it will affect the instrument and possibly damage it. Guitar manufacturers maintain a humidity level of around 45% (it varies a little from one builder to the next.) It's a good level to try and maintain.

If the wood gets too dry it might crack. Wood shrinks across its grain when it dries. The soundboard is the most likely part of an instrument to be damaged, and the back next likely. Braces that run inside across the top and back don't allow them room to breath much - to shrink and swell with changes in humidity. On violins, the saddle (the piece of ebony inlaid at the bottom of the soundboard) can cause a crack if the soundboard dries and shrinks.

You can check for the effects of unusually dry conditions by: 1) feeling for fret ends sticking out along the side of the fingerboard. 2) on a flattop guitar, looking across the soundboard in front of the bridge to see if it has sunk. 3) check for action that has gotten lower 4) again on a flattop guitar (or mandolin) sight along the edge of the fingerboard form the peghead to see if it curves up the meet the body and then drops again to the soundhole. 5) with a violin or other string instrument, listen for an uncommon thinness or raspiness in the sound, which can occur with a dry instrument.