2-Scoops wrote: ↑Fri May 06, 2022 4:13 pm
Fuck knows about ec and ac fans and which to buy or does it fit in an acoustic silencer, man im clueless, fan i have in atmo is German made hybrid fan which is twin speed running of a variac, so tis well silent tbf but i like total silence or close as we can get it hey..
I think ec fans mainly get rid of that low speed whine/hum from the electrics.
think of a dimmer on a wall, all that does is reduce the amount of power to the light and causes it to dim. That’s how ac fans work and the reason they make the slow speed noises, my lights buzz when I dim them to the lowest setting.
Ec fans work by pulsing the electric, it’s called pulse width modulation or pwm, from what I gather they have two circuits in an ec fan, one low speed which uses pwm and stops the slow speed noises, then for faster speeds it switches to a different circuit with higher output, possibly ac I’m not sure.
I’d say if your variac is doing a good enough job of reducing slow speed fan noise and it’s just the noise of air you need to get rid of then an ec fan might not make a difference for you, you need to work on silencing other things.
Look at those inline carbon filters we was talking about earlier In the thread, I reckon if I put one of them in the loft before the fan then run some ducting into the tent, then a nice big chunk of foam carved down to the shape and size of a carbon filter to fit in the end of the duct. I reckon that’ll be dead silent, the foam will act as a dust filter too.