I just run a fan and point it towards the wall. I have never liked any of the speaker-based noise machines.
Now imagine you put a filter and instead all of the dust the fan stirs up in your room, you now breathe a particle-free air ? Who wouldn't want that ?
Now imagine you put a filter and instead all of the dust the fan stirs up in your room, you now breathe a particle-free air ? Who wouldn't want that ?