I bought a large soldering iron air purifier and it turns out to be great; it has a continuious speed selector, easy to replace filters, and very pleasant spectrum. I like it better than the air conditioner, which cycles on and off noisily.
One of the best air purifiers you can get (linked in the above writeup) uses PC fans and a custom controller where you can control the speed/volume: https://housefresh.com/best-air-purifiers-we-tested/#2-best-...
One of the best air purifiers you can get (linked in the above writeup) uses PC fans and a custom controller where you can control the speed/volume: https://housefresh.com/best-air-purifiers-we-tested/#2-best-...