SoundCloud's Go streaming service is barely half a year old, but the company is already determined to attract hesitant listeners. It's launching a week-long promo that will give you 3 months of unlimited, ad-free music for 99 cents (or 99 pence in the UK) if you subscribe by September 19th. That's similar to offers we've seen from the likes of Google and Spotify, of course. However, it's more important here. While there's a real chance that you have at least a passing acquaintance with Google Play Music or Spotify, SoundCloud Go is relatively new and untested -- this is your chance to give it an extended try without dropping $30/£30. And when SoundCloud hasn't had much success getting customers to bite, a good deal like this could go a long way toward improving the company's bottom line.