Giant Denman Horn goes on display at Science Museum
When it comes to audio technology, we've come a long way from two tin cans and a piece of string.
Today's scientists can cram tiny speakers into wafer thin televisions and tablets, and achieve outstanding quality from headphones you can put inside your ear.
But more than 80 years ago one piece of sound equipment was just as revolutionary, although it wouldn't fit inside your house, let alone in your ear.
Tim Muffett reports.
20 May 2014