I think the solution to your problem is an outer case; this will make
a HUGE difference in tuning stability, and not just during these
periods of dramatically shifting weather. The case acts as a buffer
to slow things down, and what you'll find most likely is that if you
tune the instrument at 10 a.m., say, it will be in tune every day at
10 a.m. I'm playing-in a brand-new 17th-century-style French double
right now, and it's sitting next to my front door. It makes an
enormous difference in how frequently I'm tuning if I just keep the
lid closed when I'm not playing it.
>It is said that "a cold front" is moving through Eastern Michigan. Indeed,
>it has been moving through for the past fourteen hours, with gales to show
>My Italian harpsichord, which is encountering its first change of seasons
>since I strung it, is complaining. Even with newish house and central air
>heating, it is going flat and sharp on alternate days as the weather
>changes. Whereas up to now it has been pretty stable, I am getting swings
>of over 10 cents (c.3 Hz at around 440Hz). The whole band moves, but not
>totally in sync, of course, so I am having to tune every time I sit down to
>play, and I am actually wondering if I am exacerbating the problem
>by doing so.
>The instrument is of the traditional light Italian construction and is not
>in an outer box. Every time I read the thermometer it seems reasonable:
>17-20C and c.48% RH.
>Has anyone else here dealt successfully with this problem?