You can experience this in a very un-subtle way with a guitar (especially if you lower the tuning). Plucking a string hard makes it go very sharp at first, befo

You can experience this in a very un-subtle way with a guitar (especially if you lower the tuning). Plucking a string hard makes it go very sharp at first, before it settles to "the" pitch. Basically the only way to get an unchanging frequency from a stringed instrument is with a bow or some kind of external oscillator like feedback. Putting a guitar in tune has a lot to do with hard you plan to strike the strings after tuning is done.