What is the minimum decibel level required for a car alarm sounding at 60 decibels to be perceived as louder after being increased?

To determine what decibel level is required for a car alarm sounding at 60 decibels to be perceived as louder, it is important to understand the concept of the just noticeable difference (JND) in sound perception. The JND for sound is generally related to the logarithmic nature of the decibel scale, meaning that an increase of approximately 10 decibels is typically perceived as roughly "twice as loud" by the average listener.

In practice, for sounds around the level of 60 decibels, an increase of about 10 decibels (to 70 decibels) would be perceived as a significant change in loudness. However, research indicates that a smaller increment, changing from 60 decibels to about 62 decibels, might begin to be perceptible. Yet, to clearly perceive a distinct difference in loudness, a larger increment is typically necessary.

Based on common thresholds of perception, increasing the sound level to at least 65 decibels would create a noticeable change in how loud the sound is perceived. This understanding leads to the conclusion that a loudness increase to 66 decibels would definitely ensure that the sound is perceived as louder compared to 60 decib