Which of the following is NOT a factor that influences loudness?

• A. Amplitude of vibration
• B. Distance from the source
• C. Ears' perception
• D. Frequency of the vibration

Answer: (D)

Loudness comes from the energy a sound wave delivers to the ear. The bigger the vibration’s amplitude, the greater the pressure fluctuations in the air, and the louder the sound we perceive. As you move away from the source, that energy spreads out over a larger area, so the pressure changes reach your ears less, making the sound softer. Our perception of loudness also depends on how the ear responds to the sound, which can vary between people.

Frequency tells us how often the air vibrates each second, which is tied to pitch, not how much energy is carried. So, while the ear’s sensitivity can cause some variation in perceived loudness at different frequencies, the basic factors that set loudness are amplitude, distance, and how the ear perceives the sound. Frequency is not a primary factor in determining loudness.