Need quiet fan with ONLY airflow noise?

[Qwobbler]

Hey, been using a 150mm Silenced Hyper Fan for only 1 year.

 

It is now extreemly loud. It vibrates, makes a jet engine swirling noise and also a slight periodic grinding noise.

 

We have 2.5m of acoustic duct either side of it plus a carbon filter.

 

Would this be quieter?  http://www.ebay.com.au/itm/131898208268?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

 

 

he has them in 150mm aswell without a speed controller. They are $229 RRP and he is selling due to last stock and new models.

 

Any other suggestions on a Fan, preferably 150mm (will go upto 200mm if it means it will at least 50% quieter) 

 

Budget no more than $300

 

I really like the Blauberg http://www.ebay.com.au/itm/Blauberg-Sound-Insulated-Iso-Mix-2-Speed-Exhaust-Fan-150MM-353CFM-33dBA-/261942353068

 

But wow, double the price???  can we make a cheaper on just as quiet?

 

Cheers 

[Sir PsychoHashy]

If it's vibrating badly and making grinding noises you probably should be contacting the supplier or manufacturer and seeing if it's still under warranty.  As for the jet engine noise, yeah they make that, especially at full speed, but a silencer after the fan and a metre or 2 of acoustic ducting pretty much takes care of it.  Having said that, the jet noise is worse on my 150mm than my 200mm. 

 

I run the 200 in my big tent, with a silencer after it, and insulated ducting.  It works well enough that I never need to run it even close to full speed, and the only noise outside the shed is airflow when it's turned up a bit.  150 is the same but I'm running it in a light load setup so it never needs to be running very fast.  I used to run the 150 in the big tent, and the noise reduction from replacing it with the 200 is substantial.

 

My recommendation would be to go bigger than you need and dial it back if you want stealth.  Blauberg also have a good rep, and I've heard great things about Whisper fans.  But all mixed flow fans will make a bit of that jet turbine whine noise as far as I can tell, so a silencer and insulated duct are still worth having.

[itchybromusic]

might be something wrong with it 

youtube recording studio air con installation  

they can not have noise in the booth but need air con in there

you need to mount bits of foam inside each length of duct 

with each bit of foam & duct turned 20 degrees or something like that 

here ya go https://youtu.be/jkSj4Ntd0PQ

[Qwobbler]

mmm cant find the website.... found the phresh filter website but there are no fans on there?? diff manufacturer.. also cant find my recipt :-/

[phenix]

hey quobbler... I'm no expert but I've recently installed a carbon filter and fan... from what I've researched and learnt it seems like a well silenced fan will be quieter than the most expensive un-silenced fan.  And that using accoustic ducting has an even greater impact on silencing the fan than silencing the fan itself.

 

So I will be going that route and will report back as to how effective it is.  The fan I purchased was http://www.ebay.com.au/itm/191495677108?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

[Faith]

+1 Nice fan PHenix...IMma going one of those instead of the hyper - good review/reports and well a hundy or so cheaper.  I believe you are correct about well silenc ed fans...I had a little can rk 125 which with a bit of work, and reversing the flow bklowing out through the cf on top of the tent/cupboard like 'Nibs tute) I could get it very quiet...I think the sound figures were about 49 db on the box but after a bit of work all I could hear was the fridge going upstairs

 

for mine in order blauberg, can then hyper.  though I'd love to buy a silenced 200mmhyperfan...but it will probably be blauberg rambling again but yeah qwobbler 30 buck cheap wall insulation and get silent

 

Faith