Us humans preserve our experiences in recordings. And when we revisit these texts, images and sounds, it can feel like a small form of time travel. In part six of our Sound of the Cities mini-series – a sonic exploration of our urban environments and their cultural soundscapes – host Tim Hinman travels to Tokyo, digging up sound recordings made 20 years back, and meeting the artist and photographer Takashi Arai. Arai takes one long exposure daguerreotype photograph and sound recording every day in locations around the Japanese capital, preserving the day-to-day goings on across this bustling metropolis.http://www.beoplay.com/soundmattershttp://takashiarai.com