1. Vibrating metal
Seven of the speakers rely on a filament called a balanced armature, a type of tech common in hearing aids; metal vibrates between a pair of magnets to generate sound. Two armatures ring the low tones (like for a bass), four do the mids (think: guitars), and one hits the highs (e.g., cymbals).
2. Moving membrane
A magnet inside a rounded metal enclosure causes a 0.2-inch-diameter diaphragm to pulse, displacing air and pushing audio toward your ears. This eighth speaker produces sound at the lower end of the spectrum, adding a visceral bass thump that you feel more than hear.
3. Bespoke ear fit
Tubes made of medical-grade PVC funnel sound from each of the speakers into one channel. To get a perfect fit, Ultimate Ears molds the housing to match a model of your ear canal. That snug connection offers the same external sound reduction as industrial-strength earplugs. This article was originally published in the Fall 2018 Tiny issue of Popular Science.
