The disappearing and unappreciated art of audible alerts

TL;DR

Intentional sound design — from railroad crossing bells to airplane bing-bongs — is a neglected art that could make technology more accessible and less annoying.

Key Points

• 1.Electronic railroad crossing bells are crude but clever safety engineering. Made by General Signals Incorporated from PVC drain pipe, bug screening, and a ROM chip DAC, they've replicated the sound of mechanical bells since the early 1990s so the warning remains immediately recognizable.
• 2.The Temporal 3 signal is the near-universal but underexplained US fire alarm standard. Three one-second bursts followed by one second of silence; its pulsing cadence cuts through background noise better than a constant tone and has been encouraged for over 50 years, yet still isn't universal in commercial systems.
• 3.Carbon monoxide alarms use a distinct four-beep pattern to differentiate emergencies. The NFPA specifies Temporal 3 for fire evacuation and Temporal 4 for CO, yet most people are never explicitly told what these patterns mean.
• 4.Airplane bing-bongs demonstrate the ideal balance of noticeable yet unobtrusive design. Using two tones at different pitches in multiple patterns, crews communicate specific needs to each other without disrupting passengers — a decades-old system most fliers never consciously notice.
• 5.Simple mechanical door chimes still outperform electronic equivalents in practical sound design. A spring-loaded striker hitting a chime bar produces a distinct, pleasant, battery-free alert that carries well without startling — checking every box for a small-shop entry alert.
• 6.Customized per-app notification sounds function as an accessibility tool, not mere preference. The presenter, who struggles to notice haptic vibration, uses sounds like airplane bing-bongs and transit chimes per contact and app, but argues this level of intentionality shouldn't require so much user effort.
• 7.Modern phone OS design creates a false choice between annoying alerts and total silence. Broken features like notification cooldown, buried volume controls, and no per-account audio cues reflect Silicon Valley's failure to consider diverse user needs and treat sound design as a serious accessibility discipline.