Edinburgh Napier University

  With many consumer devices, we can find out about their status without having to look at them directly. When a kettle clicks off, you know the water has boiled. When the toaster pops, you know the toast is ready. The gentle hum of a freezer tells you it is functioning normally. The more you use a particular device, the more you get used to its sounds. If you hear something different, like a car engine making an odd sound, it may be time to phone a mechanic. Sound allows us to get messages while doing other things at the same time. We also interpret their information about 40 milliseconds faster than visual cues. This is why, for example, athletic competitions still use starters’ pistols. This kind of communication has carried over badly to the digital era, however. Computers and smartphones may make sounds to tell us things, but we tend to silence them or reduce them to a minimum.