BenQ LW61ST Projector - Brightness
This BenQ LW61ST (click for specs) did just fine when it comes to brightness. While true that most of the competition now quotes 2500 - 3000 lumens, this 2000 lumen projector is definitely competitive. As mentioned on the first page of the review, significant dimming of the laser light source will take years of use. By comparison, with traditional lamps, significant dimming may only take months.
With a traditional lamp, projectors will lose about 50% of brightness between 2000 and 4000 hours of use, and get bright again when you change out the lamp. This BenQ LW61ST and it's LX60ST projector sibling, will only be down (per BenQ) about 1/3 of brightness when it's time to replace the light source. Of course that time is never, for most owners. Even using this BenQ projector 25 hours a week, the minimum life of the light source is 8 years. By that time, technology should have advanced enough that projectors built today will almost all be obsolete in may ways.
There is a full power and an eco mode.
Simply stated, the BenQ LW61ST measures 1485 lumens flat out (maximum).
Eco can lower brightness, while increasing the life of the light source. Any way you consider it, though, almost 1500 lumens should be plenty bright for most classrooms, training rooms and boardroom/conference room environments, with modest lighting control.
The different modes yield - as expected, significantly different brightnesses:
BenQ LW61ST Projector - Audible Noise
The specs show that in the projectors default brightness mode which is called "Normal Mode" the BenQ LW61ST produces 33dB. In ECO Mode the projector quiets down insignificantly to 32 dB per the specs. While not too loud overall, the small drop going to Eco-mode, means there isn't one really quiet mode. For your reference, a number of home theater projectors - (where overall noise (including fan noise), is considered a much bigger problem - also quote 32-33 db noise levels.
On the downside, the projector's noise has a higher pitch component - making it a bit more noticeable than the spec would indicate. In other words, this BenQ could be quieter, but, overall, is probably in the quieter half of the competition. I'm not sure I'd want this projector in a very small room, but in your basic conference room, or classroom, it should be very acceptable.
Bottom line: Audible noise is a bit high pitched at full power, a bit too much for example, in a small office space. It should be fine in anything larger. No really quiet mode.