Installed one of the four fans I ordered in a play room. The unit emits a loud, low frequency hum that is vey annoying. I returned the three others that were destined for bedrooms. The hum would definitely keep me from going to sleep. I think that the noise level emitted by these fans should be included in the description so that buyers can make an informed decision for their application. For me, the noise level is tolerable in a play room but unacceptable for a bedroom or a media room.