Somebody told me once that if you buy a medium-price hi-fi amplifier, it will come with tone controls, graphic equalisers, and no end of knobs and dials on the front so you can adjust it to exactly the sound you want, but if you buy a really expensive one it will just have a power switch and a volume control and get everything else right without having to be told.

Someone was Terry Pratchett or Neil Gaiman, in Good Omens. Crowley is the one with the amplifier.

Gosh, well spotted. Actually I have a clear memory of who it was who first said that to me, and it was an old school friend of mine and I'm sure I would have noticed if he'd been Terry Pratchett. But you're quite right, so presumably he in turn must have read Good Omens.