  Earbuds are subjected to constant use and scenarios that may degrade sound
quality. Indeed, a common fate of earbuds is being forgotten in pockets and
faced with a laundry cycle (LC). Manufacturers' accounts of the extent to which
LCs affect earbud sound quality are vague at best, leaving users to their own
devices in assessing the damage caused. This paper offers a systematic,
empirical approach to measure the effects of laundering earbuds on sound
quality. Three earbud pairs were subjected to LCs spaced 24 hours apart. After
each LC, a professional microphone as well as a mid-market smartphone were used
to record i) a test tone ii) a frequency sweep and iii) a music signal played
through the earbuds. We deployed mixed effects models and found significant
degradation in terms of RMS noise loudness, Total Harmonic Distortion (THD), as
well as measures of change in the frequency responses of the earbuds. All
transducers showed degradation already after the first cycle, and no
transducers produced a measurable signal after the sixth LC. The degradation
effects were detectable in both, the professional microphone as well as the
smartphone recordings. We hope that the present work is a first step in
establishing a practical, and ecologically valid method for everyday users to
assess the degree of degradation of their personal earbuds.
