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Soundcloud will turn six-years-old at the end of this month. It started off as a way for audio nerds to easily upload music and other sounds online -- and it has spread from there. In the last two years alone, Soundcloud's registered users have increased 400 percent to 40 million.

Alex Jung, Soundcloud's co-founder and CEO, joins Marketplace Tech host Ben Johnson to discuss the company's founding and recent success.

Follow Ben Johnson at @@TheBrockJohnson