A cellist (L.H.) from Minnesota writes: “I get all the stuff about humidity, in fact I’m a bit over the top in keeping my cello room as close to 40% as I can. I lug literally buckets of water a day there – spilling as I go – and I still have two problems. 1. At least once a season, I have seams open and need to be re-glued, and 2. My strings are always too low at this time each winter and too high in August. What am I doing wrong?”
Both things you describe are actually normal in your climate, or at least are not preventable by normal efforts. Remember that in the summer your humidity reaches 70-80%, and right now you are 40% at best, according to your letter. Your cello is gradually losing the moisture it acquired in August and depending on the sensitivity of the wood in your instrument – they do vary – things are going to contract. Hence open seams.
The string height question is an interesting one. Some people blame it all on the bridge shrinking, and to a minimal degree the bridge does shrink in the winter, but the bigger series of events is the combination of woods – top, back, ribs, block, all moving, or not moving relative to each other to force the neck angle to be higher in the winter than in the summer. Most cellists in Vermont have two bridges to allow for this: some have three. As the string height reaches critical numbers – too high or too low – a more appropriate bridge is put on.
By the way, like heart surgery and bungee jumping, I don’t recommend trying this at home. If you loosen all your strings to replace your bridge, your sound post can fall, or at least move. Have your luthier do it for you. At the same time he can do your seasonal post adjustment – critical in northern climes – and check for open seams and other cello misbehavior.
Next time we’ll talk about a topic with a little controversy – old vs. new cellos.