Dyson Purifier Hot+Cool, 61,4 dB

The Dyson Purifier Hot+Cool HP1 is a decent option for bedrooms, particularly small ones. Its quiet operation ensures you won't be disturbed at the lowest fan speed, making it a good choice for light sleepers or for a home office where you take many video calls. That said, using the heater significantly increases the noise at minimum fan speed, and its particle filtration rate is only sufficient for a small room, so don't expect it to be very effective anywhere else in your home.