Rendering mp3 audio files using Rails

Hi,I want to render an Mp3 Audio file using Rails. I have an Android App client which is used to play audio files. The server is in Ruby on Rails and am trying to use my controller to render the audio file. I have tried Rack (this is the post on Stack Overflow -> http://stackoverflow.com/questions/1407 … using-rack ) . I have also tried the code below.Routes.rb  map.connect 'play/song.json', :controller => 'song', :action => 'play', :conditions => {:method => :get}Controller  def play    render :json => {