The loudness of a sound is primarily determined by its intensity, which is related to the amount of energy carried by the sound wave. Several factors contribute to why some things make louder sounds than others:

Amplitude of vibration: The greater the amplitude of vibration of an object, the louder the sound it produces. For example, a drum struck with more force will vibrate more intensely and produce a louder sound.

Surface area: Objects with a larger surface area tend to produce louder sounds because they can displace more air molecules, resulting in a more intense sound wave.

Material properties: Different materials have varying densities and elasticity, which affect how efficiently they can transmit sound waves. For instance, a metal object tends to produce louder sounds than a wooden object when struck because metals typically have higher elasticity and can vibrate more vigorously.

Resonance: When an object vibrates at its natural frequency or a harmonic of it, resonance amplifies the sound produced. This can make certain objects or structures naturally louder when excited.

Shape and design: The shape and design of an object can influence how sound waves are produced and propagated. For example, a trumpet is designed to amplify sound waves efficiently, leading to a louder sound compared to a simple tube of the same length.

Distance from the source: The distance between the source of the sound and the listener affects its perceived loudness. Sound waves disperse as they travel, so a sound produced close to you will generally be louder than the same sound produced farther away.

Environmental factors: The medium through which sound travels can also impact its loudness. Sound travels more efficiently through solids and liquids than through gases, so an object producing sound underwater might seem louder than the same object producing sound in the air.

These factors, among others, contribute to why some things produce louder sounds than others.