makes such a difference with odors in an older office building.

I have owned 8 germ guardian towers between two homes and they have all run quietly. The new Germ Guardian AC411W is noisy. I bought 4 for upgrades to the models because the clean air flows out the top. Thet have a squealing noise and it is hard to sleep or listen to the TV. I do not recommend until they improve this issue.

It is louder than the black one I have and not sure it's doing its job.

makes clean fresh air for the home, my dentist has 3 of these in his office

Fan isn't too loud on highest setting. It's keep both of mine in my bedroom on mid setting and sleep with them both running. Highest setting is audible but I only use it when I'm not in the room and need powerful suction to clean a dustier than usual air like doing renovations in the house. This same style air filter is sold for twice its price and this one works just as good as the more well known over-priced filters which is why I purchased a second one. I may even buy a third of this very model for my living room. I honestly feel this is one of the best purifiers on the market. So far the first one I bought hasn't had any bearing problems needing to be replaced or causing squeaky sounds like other purifiers I owned and the filter gets dirty fast so I know it's working! I highly recommend this purifier if you're on the fence. I don't think you will have any buyers remorse. It works well. It even removes stinky air because I used it in a condo I rented at the beach. It cleaned the odor out in a matter of hours. I used the UV light which is another nice feature too. So make sure to buy replacement bulbs and of course filters and the carbon charcoal covers.