A family of musical instruments is a grouping of several different but related sizes or types of instruments. Some schemes of musical instrument classification, such as the Hornbostel-Sachs system, are based on a hierarchy of instrument families and families of families.
Some commonly recognized families are:
Family relationships are not always clear-cut. For example, some authorities regard families as encompassing only instruments of different pitch range that have similar construction and tone quality. They therefore, for example, do not regard the cor anglais as a member of the oboe family, because its narrow bore and piriform bell give it a distinctly different tone quality from the oboe.