Quiet and Effective - now I can sleep

Every Spring, beginning in March, I suffer from allergies that cause me to sneeze, cough, and choke so badly I can't sleep lying down. Last year, I had a Honeywell tower HEPA air purifier. It was effective at removing allergens; however, it was so noisy, I couldn't sleep. So, I did some research and, one week ago, I bought the Whirlpool Whispure 510 at Best Buy. I have slept like a baby every night since. On low speed it is still effective at cleaning the air and is also quiet enough that it does not disturb my sleep.

And a bit of advice if you're looking for a quiet machine: consider not just how loud it is (decibels), but the "quality" of the noise. If it's a high pitch whine, rattles, pulsates, or makes any irregular sounds, it doesn't matter how quiet it is, it's intolerable. I found the sound of the Whirlpool Whispure to be very pleasant and soothing.