AC InfinityCLOUDLINE PRO S6, Quiet 6” Inline Duct Fan with Speed Controller - EC Motor Ventilation Exhaust Fan for Heating Cooling Booster, Grow Tents, Hydroponics

I have to admit, when I was shopping for a power fan to vent my xTool P2 laser engraver, I was a little worried about power (would this fan give me enough?) and loudness levels (would it be too loud?) and I have to say, it's perfect on all accounts.My system is probably just as complex as you'd guess: xTool P2 Laser, connected to a xTool filtration system, and then vented outside. That's three ducts (printer to filter, filter to fan, fan to outside) at 4", and the P2 itself is natively 3", but I bought an adapter on-line to make it 4".So overall, the fan works great, like wow! You can still hear it - it's not super quiet, but it's also not annoying. It's more of a louder "whoosh" than an annoying whine, if that makes any sense? And that's me running this fan at full-power, which is basically where I'm going to keep it at. It's possible that your needs won't be 100% all the time, and it is absolutely quieter at the slower speeds.The duct connections are perfect, and the 6" to 4" adapters I purchased here on Amazon were absolutely flawless and leak-free.As someone who buys a lot of high-end computer components, one of the things I really appreciated about all of the AC Infinity products (three ducts and this fan) is that it's well packaged, with a lot of accessories. It's almost like opening an iPhone, if iPhones came in dark packaging.It's also clear what this fan was designed for, as it came with a "how to grow hemp" manual, which made me laugh.There's a nice YouTube video on-line that explains how to set this all up specifically with the P2 (with details on the 4" to 6" leak-free custom adapters), and he tells you to get this model, and not the one that has all the bells and whistles (Bluetooth, WiFi, garbage disposal, toothbrush). I'm glad I got this exact model (S6 PRO).The remote is cool, and comes with a nice LONG (9') cable so you can put this wherever you want. You press the button once to turn it on, and it remembers the last settings (1-10) if you hold the power button for four seconds to turn it off. It's pretty cool!I love the design, and the fact that you can remove the center blower, to install the bracket on the wall, and then put the blower back in. Solid build quality.Overall, I'm very happy with this blower fan, and would absolutely recommend it for hydroponics and exhaust systems.

Noise level. It's five stars for being quiet. But the massive amount of air it can move can be "noisy" like wind can be noisy.Install was completely straight forward. Easy? Well, I had to cut a 6" duct to size, removing the correct amount so it would fit, for it to be inserted in the duct line. And that entailed disconnecting the duct from the distributor and all, but completely as expected.Fan unit was light, a good thing, but build was solid & strong. Well made, sturdy.Now how it changed our lives. With our inhabitable, exposed basement we have a four story house with the "primary" (master) bedroom on the third floor.When we built the house we couldn't afford central A/C, so the ducting was prepared for it, but a bit under sized. Once we put in central A/C it was very difficult to drive cold air up to the upper floors. The "basement" would be cold and the rooms on the main floor would be fine and the thermostat would stop the A/C.We installed an in-line sheet metal 240 cfm Vivosun unit. It rattled & moved little air... it was cheap, but junk. We resorted to floor fans trying in vain to push cold air up the stairwell to the bedrooms.This AC Infinity is worlds apart. We have two. The variable speeds and control unit are wonderful. At full tilt we can push as much cold air as is needed, balancing the temperature between floors and sleep in comfort.Your situation may be different. But for us it's been a life saver, and brought comfort to all the upper rooms, eliminated floor fans and is saving us money. We couldn't be happier.p.s. pre-sale and post-sale customer & technical support are superb.

DAY 1: WHY I BOUGHT THESEI bought these hoping to find a 6" fan that could move some air gently, without causing the sound and fury of a small cyclone in my recording studio. With voice over work, extraneous noise is a problem. So is heat, and air!, because VO rooms are usually completely closed off the the outside world. They get hot and stuffy without proper air flow.This is the answer. I have tried 6 different claimed-to-be-quiet fan solutions via Amazon and YouTube reviews... this is unequivocally the best for my situation.I unboxed and hooked one of these up (not to my room, because that will require some ducting and electrical changes) in an untreated echo-y basement room with a hard tiled floor. So no mounting yet, no ducting yet, just the fan on the floor with its 10-level USB-C controller, and me holding my iPhone running the app "SPLnFFT" noise meter at about 12" above the center of the fan, airflow running unimpeded from left to right on the floor, The iPhone was held level so I could read the display.Here are a few hasty values.Starting point: Fan at 0 = 30db (A) This is the room's noise floor when nothing is turned on. The meter terms this level as "Almost Silent".Fan at speed 1 = 37db (A) The meter calls this "Very Quiet".Fan at speed 2 = 45db (A) The meter labels this "Quiet."Fan at speed 3 = 53 db (A) "Comfortable"Fan at speed 4 = 60 db (A) "Moderate"ASIDE: Note that these levels are purely "in the moment," not carefully measured. Use these approximate numbers as a rough estimate only if you are similarly seeking a quiet, controllable fan solution. I did "round off" to the nearest dB, so 37.2 became 37.Keep in mind I intend to use 2 of these fans, 1 to send fresh air into the booth from floor level, and 1 for pulling warm air out of the booth above eye level. I don't want a wind tunnel, simply fresh air moving through the space via insulated, flexible ducting to help keep the air flow noise reduced as it travels into and out of the booth. I anticipate that once installed, I can record spoken/sung material without concern for air noise.Even at speed 1, the air flow felt pretty good. At the next higher settings, it grows noticeably stronger. I only ran through speed settings of 0 to 4, because at 4, I figured I was getting to "you're gonna hear this" territory and decided not try any higher settings. I would not record with air flow noise. But I did step though the rest of the settings, because the fan controller only increases the speed (no going down, only up) until the step after 10, which is off, so I got hear and feel those levels even though I was not interested in measuring them.A pair of these fans will clear the space pretty easily.THE FUTURE: AFTER THE INSTALL, and LONGEVITYI plan to return and update this first-look review with genuinely measured results once the booth is complete. That will likely be another few months because... life, family, and holidays. And if anything fails (controller, fans, whatever) I'll update this then, too.