When it comes to iconic London sounds, the oscillating whoosh of the Jubilee line is right up there with Big Ben and ‘Mind the Gap’. Sounding more like the Tardis than a train, this mysterious and haunting sound isn’t heard anywhere else on the tube network.
But have you ever wondered why a Jubilee line train pulling out of the platform sounds like the Millennium Falcon hitting .5 past lightspeed? I have, and the fact that there’s a Google autocomplete for the question ‘Why does the Jubilee line make that noise?’ suggests that I am not alone. So I enlisted John Bull – the man behind the fabulously geeky transport website London Reconnections – to answer this engineering enigma.
The answer, apparently, is the need to make sure that the sounds made by accelerating trains don’t bugger up signalling on the tube network, as John explains. ‘Making trains move is harder than you might think,’ he says. ‘Not only does it require complex gear systems, but you also have to make sure that nothing produces magnetoresistive noise on frequencies that’ll disrupt the signalling system. The Jubilee line “tune” is the result of doing all of that with the technology available when the trains were built in 1996.’ So that weird sci-fi noise is what happens when you need to make a train go, but also need to avoid certain other noises.
And while the Jubilee line trains are unique in London, John points out that the same engineering problems have been tackled more creatively elsewhere. Instead of a Jubilee-esque whirr, the Siemens Taurus train in central Europe plays a two-octave musical scale as it pulls in to or out of stations. The saxophone-like noise has become so popular in Austria that the federal rail company ÖBB released it last year as a downloadable ringtone. Your move, TfL.
For more geeky London stuff, sign up here to get Time Out features straight to your inbox.