The Modem Dialup Sound, Visualised

Remember the dialup sound of your modem from back in the day?

Those beeps and glitches aren’t just random garbage, but they’re the handshake between two modems trying to agree on which language they’ll be speaking to one another.

Oona Räisänen has created this nice poster of a spectogram of said handshake, detailing what each blip stands for:


The sound of the dialup, pictured →