Idiophone and most membranophone pitch cannot be controlled by the player

Evidence

The pitch produced, if any, by idiophones is, in most cases, not controllable. In membranophones the pitch is defined by the properties of the membrane and the enclosure. In most cases it cannot be controlled, although exceptions exist. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 676

Categorization

• corroborated: 2 independent passages support this claim — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 676