Empirical Analysis of Earbud Output Levels Across Various Devices for User Safety

Earbuds are recognized for their ability to eliminate or reduce surrounding noise, allowing users to concentrate on specific tasks. However, this primary function can be compromised by introducing additional hazards when used across multiple devices. This study examines the variability in decibel (dB) outputs of a single pair of earbuds across three different devices while maintaining the same volume setting. The earbuds chosen for this investigation were the Billboard model, commonly used on airlines, and tested with a laptop, desktop, and a cell phone. To measure the output of the earbuds, a GRAS 45CB Acoustic Test Fixture was employed. All devices were procured from a retail store to simulate typical product usage. Data collection took place in a controlled acoustic laboratory. The results indicated that, at each tested volume level, the average difference in dBA between the left and right ear was 3 dBA or more. Furthermore, the analysis revealed that 23% of the output readings for the right ears between devices and left ears between devices collected by the GRAS 45CB from the earbuds at volume levels of 20, 40, 60, 80, and 100 across all devices fell below 3 dBA. In contrast, 47% of the output measurements surpassed 10 dBA. Moreover, 30% of the average output differences were recorded at 3 dBA or higher. The National Institute for Occupational Safety and Health (NIOSH) recommends that for every increase of 3 dBA, the recommended exposure time should be halved, which aligns with the just noticeable difference (JND) threshold for human sound detection. The findings from this study reveal that the Billboard earbuds do not provide a consistent output across different devices at the same volume level. Consequently, the researchers advocate for an intervention to standardize the design of earbuds to enhance user safety.