The noise levels of 13000:1 contrast ratio projectors that were released more than two years ago range from 26dB to 40dB, and the average noise level is 33dB. With a noise level of only 30 decibels, the Optoma EW556 has a quite quiet noise level compared to most of the other similar spec projectors that were released more than two years ago.
It may also be worth also looking at one of the alternative 30dB noise level projectors currently available including the Benq MX503 which has better reviews.
If you would consider a multimedia projector with a louder noise level then you might want to look at the Optoma EX556 (£241.74) (30dB).
What does "noise level" mean?