Changes

''Strings resonate at a certain pitch, depending on the '''thickness, length, and the amount of tension ''' applied to the string.'' The thicker and longer the string is and the lower the tension on it, the lower its resonant pitch is, and vice versa. It is important to realize that this simple formula isn't absolute - there are some very nuanced complexities to the physics involved; however, the relationships are good enough to be perceived as completely accurate. For guitar and most instruments, the strings have different thicknesses but relatively the same tension. Thus, the thicker strings have lower pitches than the thinner ones. The even tension makes playing (and especially bending) the strings have a consistent difficulty from one to the next. The primary method of altering pitch is by shortening the string length by pressing the strings against the frets or fingerboard. However, other methods are also used - for instance, in electric guitar a whammy bar or bending technique may be used to reduce or increase string tension. In contrast, the piano matches each of its keys to an independent string of fixed length.