They are virtually silent..with an occassionl random "spin-up"..I'm trying to think if it ever makes much noise, because if it did, it's one of those things that you eventually "stop hearing" because you get used to it. The iBooks on the other hand, are noisy..sometimes very noisy with an almost clunking-chunking-banging noise because the CD drive doesn't close fully and flush unless you really push it..but anyhow..