how loud 45-50 db fan ? - Page 1
Forum section: electronics / beginners

author: nour
author_rank: Frequent Contributor
timestamp: February 19, 2016, 09:43:57 pm
content: I am not sure if this is the right place to write this topic, so if not please moveI want to buy ac fan like this onehttp://www.tme.eu/en/details/uf13a23-h/ac230v-fans/fulltech/uf13a23bth/I want it quiet as possible but also maintain a good level of air flowI have compared it with this onehttp://www.tme.eu/en/details/dp202a2123mbt/ac230v-fans/sunon/dp202a2123mbtgn/but I don't know which one should I buyI am going to build one like thishttp://www.tme.eu/en/details/wel.wsa350eu/soldering-fume-extraction-systems/weller/wsa350eu/this is fume extractor which cost around 83$doesn't include shipping and I can build it under 20$(including the filters and the enclosure)I want to have a good air flow and quiet as possibleany advice ?

author: Rerouter
author_rank: Super Contributor
timestamp: February 19, 2016, 09:48:22 pm
content: 18db is the line i draw to be able to sleep near to, 50 is about what a video card sounds like on full tilt,

author: nour
author_rank: Frequent Contributor
timestamp: February 19, 2016, 09:51:26 pm
content: Quote from: Rerouter on February 19, 2016, 09:48:22 pmvideo card, do you mean computer VGA cardif so that's actually very loud

author: ataradov
author_rank: Super Contributor
timestamp: February 20, 2016, 12:00:07 am
content: 50 dBA is LOUD. 40 dBA is a normal office noise level. 50 dBA of constant noise will induce fatigue.

author: nour
author_rank: Frequent Contributor
timestamp: February 20, 2016, 12:21:45 am
content: I Think I will buy the higher one and add speed controller later if I found it not comfortable

author: Paul Price
author_rank: Super Contributor
timestamp: February 20, 2016, 12:28:14 am
content: You will be quick to notice that using more than one fan, each smaller but each running at slower speeds results in a much quieter, less-maddening experience. The faster the fan the bigger the noise.

author: Skimask
author_rank: Super Contributor
timestamp: February 20, 2016, 12:29:21 am
content: 10db louder than a 35-40db fan?

author: LaurentR
author_rank: Frequent Contributor
timestamp: February 20, 2016, 12:39:22 am
content: 50dBA is incredibly noisy for a fan.I also like to keep my fans to below or near 20dBA if possible.If you look at the Weller datasheet, it says the fan does ~75 m3/hThe incredibly noisy Fulltech fan you link to does 175 m3/h, which is quite a bit more, but even slowing it down to something equivalent will not net you anything bearable.Now, looking at properly low-noise fans, the Noctua NF-A14 ULN can do 80 m3/h (about as much as the Weller) at 11.9dbA, which is basically inaudible.Without going to the Noctua range, which is the golden standard in quiet fans, you can find PC fans of 120-140mm diameter that will push as much airflow as the Weller extractor at <20 dBA, where most of the noise will come from the filter air flow impedance, not the fan.

author: nour
author_rank: Frequent Contributor
timestamp: February 20, 2016, 12:49:26 am
content: Quote from: Paul Price on February 20, 2016, 12:28:14 amthat's actually very nice ideaI will give it a try

author: rich
author_rank: Frequent Contributor
timestamp: February 20, 2016, 03:35:47 am
content: Can I ask a (possibly stupid) question about how to read fan noise specs? Is the dbA figure quoted in the data sheet right by the fan, or is it a fixed standard distance away?

author: Rerouter
author_rank: Super Contributor
timestamp: February 20, 2016, 04:12:41 am
content: It appears from digikey of all places that a normal distance for the sound rating will be taken at 1m

author: rich
author_rank: Frequent Contributor
timestamp: February 20, 2016, 04:23:50 am
content: Thank you, that's good to know. I shall now take readings of my troublesome power supply at 1m distance as a baseline for replacement fan shopping.