I'm using objective C to parse the data (programming an iPhone app). It's the returned JSON file which is 0.5MB. The analysis URLs are provided after a song/playlist request and expire after 10 minutes.
They look like this: http://echonest-analysis.s3.amazonaws.com/TR/2b6g4AxI_9ukP3AZQjrhho5zlbkvbZdeUY27iSxauM1D93rrGAP6jx2P8raKT9u4wA8j_hVhbd0DoeZvs%3D/3/full.json?AWSAccessKeyId=AKIAJRDFEY23UEVW42BQ&Expires=1427624347&Signature=TJeZ44//g7Ay5P/wTFtyUMQQRxQ%3D