I've tried an Active Air speed controller with my new 4" Can Fan S400 and I'm getting a lot of buzzing/hum with the combo. The buzz/hum is constant and not dependent on the speed setting. In the medium range the buzz is as loud or louder than the fan. My electrical system isn't that old (regular 3 prong) and I've tested the outlet with a plug in tester, and everything is normal.
With my trusty old Superior variac there is no buzz. The sweet spot is 70-75 volts with decent airflow and not a lot of noise. Below 70 volts the fan start shutting down, so you can't run it super slow. The fan is listed by the maker at 126 cfm, so even with reduced airflow it should be good with smaller spaces.
As far as the Can Fan, it looks like it's good quality. Maybe someone who's been using one can chime in as far as reliability. The only issue I've seen is the intake flange at the rear seems to be very slightly tapered and a circular band type clamp wants to slide off if it get's pulled on very much no matter how tight you clamp it.
I tend to get hung up on playing with gear, if I ever get some seeds and my grow area set up it'll be interested to see how the fan works for real.
With my trusty old Superior variac there is no buzz. The sweet spot is 70-75 volts with decent airflow and not a lot of noise. Below 70 volts the fan start shutting down, so you can't run it super slow. The fan is listed by the maker at 126 cfm, so even with reduced airflow it should be good with smaller spaces.
As far as the Can Fan, it looks like it's good quality. Maybe someone who's been using one can chime in as far as reliability. The only issue I've seen is the intake flange at the rear seems to be very slightly tapered and a circular band type clamp wants to slide off if it get's pulled on very much no matter how tight you clamp it.
I tend to get hung up on playing with gear, if I ever get some seeds and my grow area set up it'll be interested to see how the fan works for real.