require 'soundcloud'

#create client with your app's credentials 
client = Soundcloud.new(:client_id => 'YOUR_CLIENT_ID')

# a permalink to a track 
track_url = 'http://soundcloud.com/forss/voca-nomen-tuum'

# resolve track URL into track resource 
track = client.get('/resolve', :url => track_url)

# result: "SoundCloud::ResponseError: SoundCloud::ResponseError"