The average noise level of projectors of this type and age is 37dB, and the noise levels range from 28dB to 73dB. When compared to other projectors of this age and type that we have checked, the noise level of the Optoma X310 of only 28 decibels is one of the quietest.
There are a number of other 28dB noise level multimedia projectors currently available that you might want to look at including the Asus P1 which has better reviews.
Multimedia projectors with a louder noise level that might be worth looking at include the Sony VPL-FX35 (£1,287.96) (31dB).
What does "noise level" mean?