The less mass a string contains, the faster it will vibrate. The result of such a fast vibration is a high-pitched sound. This can be seen in many instruments. For example, the larger note blocks of a xylophone produce lower sounds, whereas smaller blocks produce higher sounds. 

Similarly, the shorter a tube is, the faster the vibration inside it is. The result is a high-pitched sound. The function of the pan flute is based on this phenomenon. 

The length of a tube can be adjusted with water (such as in water flutes) or by opening holes inside the tube (the recorder and the flute). If a tube consists of two parts, it can be made shorter by pressing one half of the tube inside the other half (such as in the slide trombone). 

The shorter and thinner a string is, the higher the sound it produces is. The strings on the left-hand side of the piano are longer, which means that they produce lower sounds than the shorter strings on the right-hand side. 

The pitch of a sound can also be adjusted by tightening the string. This is done with many stringed instruments, such as the guitar or the violin.