the origial version is quite lound since it is 440W ,  modified version is pretty quite ,more or less  as anminer S3+, don't have the tool to test to know how much db.
see the pictures , I am just sitting at 3 meters  away from this five miners , it is OK for me .

http://i1066.photobucket.com/albums/u410/picshare321/sf_zpsrch67e4v.jpg