JVC DLA-X55R Audible Noise
For a large projector, it's not as quiet at full power, as you might expect. It's not bad though. Probably high - right around 30 db is my guess. It's definitely a little quieter than the Epson UB projectors and noisier than the Sony HW50ES (and likely the VW95ES - but it's been quite a while since I played with the 95ES.)
Switch to Low power, and the projector becomes very reasonably quiet - no issues there, not even (I think) for those most sensitive to audible noise.
Back to full power. When the JVC's running in High lamp, sitting 3 feet from the projector, it's fan noise is almost completely drowned out by my Sony PS3 when its fan is on high. The PS3, however sits 8 feet from me. As with most projectors, we could hope for quieter at full power, but mostly you won't notice it - it's steady, and relatively low pitched - unless you hit a really quiet scene. Even then, it's likely to be like sitting in the kitchen - you tend not to notice the sound your refrigerator makes when running - at least not until it turns off, then you think "ah, the refrigerator noise just went away".
No more issues with audible noise than other projectors in the price range, and a little quieter than some.