Why can a new product have a lower decibel level, but still sound worse than the previous generation?
Answer: Tones!
A tone is a single distinct frequency that stands out when listening to a product. Imagine a whistle, pitch, or whine. Even at a lower decibel level, this can be more noticeable and possibly more annoying that a louder, higher decibel level, broadband sound.
This seminar covers tonal metrics including Tone-to-Noise Ratio, Prominence Ratio, and Tonality.
