How can an instrument’s loudness be changed?

Question

the energy of the vibrations is changed
the type of music played is changed
the tones are varied and changed
the type of original energy is changed

Answer 1

An instrument's loudness can be changed by adjusting the amplitude (height or intensity) of the waves it produces. This can be done by striking the instrument with more or less force or by changing the amount of air pressure applied to certain types of instruments. Another way to change an instrument's loudness is by adjusting the distance between the instrument and the listener, as sound waves lose energy the further they travel through space. However, changing the type of music played or the type of original energy won't necessarily affect an instrument's loudness.