Fan Noise ?

The grow room doesnt have to be stealth for legal reasons, but it exhausts into the garage, and since I like to tinker, it would be nice if the fans were quiet.
There is an 8" turbine fan mounted in the side of the garage wall a little below eye level. Question is, how does a person go about quieting one of these things down?

Either speed it down w/ a speed controller, mount with anti vibration mouting hardware if not done already (rubber washers, maybe bungee hanger, wutever) if thats all still no good... move the exhaust to the ext. of the house... 8" is a big hole, but I just use a board in my window as a temp. exhaust port to avoid the 6" hole I got.... I too am MMMP and need not be stealthy.

Bottom line tho, to keep temps down, air must move, faster it moves, more noise it makes...

Oh, and replace as much flexi venting as possible to rigid, each little ridge inside that vent is reducing air flow, and increasing noise.

It's not a vibration issue at all, it's that I can literally see the fan blade. The sound of it, and the air it moves is quite intense right out of the nozzle. I tried an elbow, but that didnt help much.

build a dampner, or muffler. I used it when I vented into the garage which is right next to my office. Its a pretty easy DIY project, and it can also be used on the exhaust the same way you would connect a carbon scrubber, without the heaxy carbon to push through. It will reduce your airflow though, so you may need to increase the speed to compensate (if you are on a dimmer or Variac)

Here is a carbon scrubber I made, later converted to a muffler because I wanted a larger scrubber.

https://www.rollitup.org/t/ultimate-diy-carbon-filter.649682/

Helped the noise a lot.

44 plastic drum that I cut around the circumference, stuffed full of insulation cut a 150mm hole in either end and placed the fan inside that with chicken mesh creating the 150mm tube through the drum. Sits above head height.

At full noise, whisper quiet.

This s-line is so quiet and moves air really well. No joke, I'm sold on these mothers. I see more companies doing the same design, haven't tried any yet. I run it full tilt during lights on next to me and my girls bed (no complaints from her even). Keeps my 600w 5x5 at about 74-78° at flower tops 10" from tube. And when I turn it down at all I have to feel it to make sure it's running, so you can't hear anything while it ventilates during dark cycle. Anyhow...I'm careful with money and I don't regret buying it.

I just play ACDC in the background...it cover's the noise & the plants love it!

Zaycor said:

I just play ACDC in the background...it cover's the noise & the plants love it!

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Nice, me and the girls had a megadeth session the other day. If neighbors don't complain about that

Sounds funky...& if the neighbors moan about the noise then at least they weren't complaing about whatever it is your growing in the back!

I definitely have come to the right place to quiet down my fan noise. When it comes to making a DIY muffler, can someone give me a bit of a rundown as to what's necessary? I just got my new 190cfm 4inch fan hooked up this morning and as soon as I turned it on my girlfriend gave me the look... So it needs to be quieted down a lot. I plan on replacing my flex ducting with something rigid like suggested and am getting a speed controller (Next paycheck). But the muffler I can make now!

I included a link up above for a DIY muffler I made. Just leave out the scotch brite bag of active carbon and you got your muffler. If you are running at 100% speed on a bigger fan, it may not completely eliminate the noise though

hbbum said:

I included a link up above for a DIY muffler I made. Just leave out the scotch brite bag of active carbon and you got your muffler. If you are running at 100% speed on a bigger fan, it may not completely eliminate the noise though

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Wow haha I completely overlooked that. Thanks!

Last spring, I had to replace the carbon filter, when I had this feeling I shouldn't throw it away. I used it to make a muffler with, half the work is done. Just drilled out the pop rivets, spread the carbon in the gardens, stuffed it loosely with sound deadener, and reassembled with self tapping screws.

roldgoldrlg said:

Nice, me and the girls had a megadeth session the other day. If neighbors don't complain about that

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I have to be careful when touching the volume on the Perreaux 250i amp and Revelation2 speakers........the back neighbour remarked Sixto Rodriguez sounded excellent and he had not heard that since the 70's.......problem with that is, he lives 200m from the back fence !!!!!

East Coast said:

I have to be careful when touching the volume on the Perreaux 250i amp and Revelation2 speakers........the back neighbour remarked Sixto Rodriguez sounded excellent and he had not heard that since the 70's.......problem with that is, he lives 200m from the back fence !!!!!

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Love it! That's hilarious...I had a landlord come knocking after a girlfriend and I broke out my vinyl. I thought a neighbor complained about the smell of the flowers, when he asked if I could transfer 4 records at a time (60-70's era) to cassette in return for a sack of our maintenance guys home grown

Mufflers and any other sound control device generally just slow the air down. Sure its more quiet now with these attached, but your air intake/exhaust is now moving slower.

Best solution I've found, is if you need a 6" fan, get a 10' fan and speed control it way down. Then you always have enough air flow, and is now much more quiet than any muffler I've ever heard. A muffled 6" fan running balls out is MUCH louder than a speed controlled 10" fan.

Think about, blow through a straw as hard as you can, then blow through a paper towel roll. Which method was louder, and which method exhausted your lungs faster?

Hi. Use insulated ductwork, try bigger fun with good speed contoler. Try not to move air so fast, use bigger diameter ducts , smooth path. Hang fun on rubber. You can buy duct silencer in hvac shop.