Real Power Chords
Listening to music on a headset while you're out walking sometimes leads to surprising dialogs between the music in your ears and the sounds and sights from the world around you.
I had exactly that experience this morning, listening to Boards of Canada's track Skyliner from the album Trans Canada Highway. I was in the Montreal Metro's orange line and the train heading in the opposite direction was just pulling out from the station. The metro gives off a little three-note quint arpeggio as it pulls out - root, quint, octave - a power chord if you're a guitarist, and it just so happened that this chord matched a part of Skyliner so perfectly it was eerie.
This arpeggio sound is the power being switched on sequentially to give a smooth start, and is actually explained on the Transport Society's web site along with the fact that the wooden brakes of the metro is lubricated with peanut oil to give off a pleasant smell when used. I've got some smelling to do next time I take the metro!
