Made more versions of the CR Box posted here previously https://www.reddit.com/r/crboxes/comments/1sb9ths/smart_home_crbox_controllable_with_home_assistant/
For the new version I moved the back fan to the front since that makes more sense, I want air blowing into the room.
My first version I covered in white vinyl sticker for a different look.
Hi guys! Bought 4 Ikea FÖRNUFTIG filters and discovered by mistake that if I arrange them in this configuration, inside it's enough space for 4 x 120mm fans.
To stick the filters together, I've used good old hot glue gun.
It took me some thinking of how to manage the PSU, as I didn't want to put it inside and waste so much space. Also, I wanted a way to easily change the filters, so I've used velcro between the layers.
I know that the PSU is such an overkill, but I haven't found in Europe an easier way to power the fans.
As I want to give it to my mother, I searched for a way to protect her fingers from the fans and the PSU. I found this cheap mosquito net that comes with velcro.
I'm waiting now for some parts to convert it from the PSU to a cheap 12V charger.
So this is the final list for this version:
1 x Mosquito net with velcro
3 x Birch wood shelf - 28cm x 28cm
3m Velcro
4 x Arctic P12 Pro fans
1 x MOLEX to 4 pin fan adapter
4 x FÖRNUFTIG filters
1 x PSU 500W
1 x PC power cable
Let me know if you have any feedback or questions. Working now on an improved v2 with a simpler power supply, fan speed control and Tuya smart functionalities.
Hello Everyone!
I'm posting today to get some insight from others on their filters and general knowledge. So here's the deal, I wanted to buy the normal version nukit tempest and I was waiting to see if it would ever go on sale. It never did and it seems like they discontinued it for the new pro which it WAY above my budget. I'm looking for a long lasting semi portable option since I live in an apartment and move from time to time. The clean air kits don't seem fit for me but I was going through the subreddit and think my next best option is 3D printing. I don't have one but know libraries more often than not have them and I think PLA filament would do just fine. Planning on using artic fans in combination with 20x20x1 MERV 13 Filtrete filters. Would love to see others peoples solutions and builds, Thank you!
In this subreddit and elsewhere, the type of noise a PC fan makes comes up more and more. And there's a recurring narrative: Arctic P14 Pro or P14 Max = the villains. Noctua = the heroes.
But the devil — or the sonic paradise — is in the details.
At what speed? At what dBA? In open air or inside a build with a filter? The same fan can sound completely different depending on the context. Two fans measured at the same dBA don't necessarily sound the same — the frequency spectrum, the "color" of the noise, matters too.
At 36 dBA, my subjective pleasantness ratings are:
Not exactly the villain/hero story people tell — at least for these fans, at 36 dBA, and in my subjective experience.
And it gets more interesting: inside my DIY HRV AccordFlow with a MERV 13 filter, the Arctic P14 Max produces a deep, calming brown noise — more pleasant than the same fan in open air.
Listen what brown noise sounds like:
https://www.youtube.com/watch?v=_t9uWUyuMUc
Listen what Pink Noise sounds like— https://www.youtube.com/watch?v=ezwIrxOFFqw
Listen what White Noise sounds like https://www.youtube.com/watch?v=sSZaNwRU-MA4
Sound color is also only part of the equation. CADR matters too.
In my test chamber, at equal dBA, Noctua fans deliver a lower CADR compared to the same device built with Arctic P14 Max fans. That said, don't generalize — I test at quiet levels (35–40 dBA), and the picture can be different at higher levels and on different models of air purifiers. Fan A may be more pleasant at low noise but the opposite at max speed.
This is just the beginning of the conversation — we need MUCH more data, from more people, in more contexts.
I hope that one day, air purifier and ERV spec sheets will include noise spectrum information — something like a "brown noise" or "pink noise" certification. Do you?
N.B. About the Youtube video “The Ultimate 140mm Fan Test”
This video is genuinely useful if you’re shopping for a PC fan to cool your computer and want to know how each fan sounds at 25%, 50%, 75%, and maximum speed. For that purpose, knowing both the dBA level and the sound character at each speed is valuable.
The video lets you hear each fan and judge pleasantness for yourself — which is valuable. The limitation is that except for the first segment (38 dBA for both fans), the other three segments don’t compare at equal dBA levels. So what you’re hearing is fans at different intensities, which makes it difficult to isolate sound color from loudness. To compare sound character fairly, equal dBA is needed first.
https://www.youtube.com/watch?v=LAVfS2ANPDA&t=3s
Hi, after learning so much from this community I have decided to make a parametric design with four IKEA STARKVIND filter and four P14 Pro PST fan. In my case, it's PWM controlled by ESP32-C6 via Zigbee set at 27%, which is silent for me, consuming 1W and 17W at max speed.
The tall tower version should be printable on a Bambu Lab A1.
Fully 3d printable with some heat inserts and M3 screw, some seal tape and hot glue.
As it's parametric, feel free to adapt for other filter size, should be generic as long it fit on the 3d printer (half size) and it's square filter.
The STL and BOM with instruction is available at: