After an unusually warm start to fall, the weather has finally taken a turn for colder temperatures here in southeast Michigan. And I have started to notice my violin going out of tune a little more than usual.
Dry winter weather can wreak havoc on string instruments. Here in Michigan, it gets very cold and dry in the winter, which is a big difference from our hot, humid summers. They don't call Michigan "the season state" for nothing-- we get all four seasons here; though winter tends to be the most pronounced!
In general, violins like a stable humidity between 40-60%. The low humidity and low temperatures can cause some issues for violin players. First, I should address the obvious: NEVER leave your violin in the car or garage overnight, especially during extreme hot and cold temperatures. Extreme swings in temperature and humidity can cause the wood of your instrument to swell or crack.
By keeping your violin in a room where the temperature and humidity don't vary much, you will greatly improve the conditions for your instrument. When conditions are stable, your violin is less likely to go significantly out of tune. Most of us here in Michigan will want to add some extra humidity to our cases. It is often easier to control the humidity in your case than in your whole house, since it is a smaller area.
There are a few different kinds of humidifiers on the market for inside your case.
1) Dampit ($12)
This humidifier goes inside your violin through one of the F holes and has a stopper so that it will not fall all the way inside. I have had a dampit for many years and still use it today. Essentially, it is a sponge encased by a rubber tube. Some people have reported their dampits leaking water inside their instrument and causing issues. I have never had that issue. To use this humidifier, just run the dampit under water for a few seconds and then wipe off excess water with a towel so that it does not drop water into your instrument. Depending on how dry the air is, you may need to hydrate your dampit twice a week or as often as once a day. The dampit comes with a card that has a humidity indicator to let you know how humid the air is. I have found this card to be woefully inaccurate and hard to decipher. If you want to know how humid it is inside your case, you're better off having a separate hygrometer. I do not have a hygrometer in my every day case, and I don't really find it essential as I can generally tell when my violin is responding to changes in climate.
2) Stretto 1010 Humidifier for Violin ($24)
This humidifier is a humidifier pack that should keep your case humidity at optimal level for up to two weeks. It is a small humidifier pack in a plastic case (3.15 x 0.78 x 2.36 inches) that goes inside your violin case wherever there is room. Stretto sells replacement packs, but reviewers say that you can re-hydrate the pack by soaking it in water if it gets dry.
3. Boveda Small Starter Kit (comes with two packs) ($23)
The boveda packs are sort of like the stretto humidifier packs, but you place them in a soft pouch rather than a plastic case. Unlike the Stretto packs, you should not resoak these. Once they are dried up, they should be disposed of. The packs last for 3-6 months. The great thing about Boveda packs is that not only do they humidify the air, they maintain a relative humidity between 45-55%, perfect for string instruments. This means that they can help with excessive humidity in the summer, too, a feature that the dampit or stretto cannot help you with.
There are some other kinds of humidifiers on the market, such as tubes that come in cases. I do not recommend those unless you modify them to prevent leaking. The dampit, stretto, and boveda systems mentioned above seem to be the most popular with my fellow violinists and most recommended by luthiers.
Do you have experience with any of these humidifiers? What do you use in your case?