Reading: "The mysterious loudness control: What does it do?"
A wonderful post on when an obscure design feature went wrong and understanding what it ever did in the first place
Have you ever seen that button on a record player or audio system labelled "Loudness" which, when toggled on, just makes the audio sound much better? This post by Steve Somers goes in to the science behind this control. To be honest, although I found it hugely fascinating, most of the content went right over my head but from what I can gather the control essentially provides more power to compensate for low frequencies which is why when switched on your audio should sound much richer.
What I really love about this post is why it was written in the first place: A disregarded simple design feature which went wrong and discovering the complexity involved to get it working.