u/CartographerLong5796

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It’s rare for a book about air quality to read like great literature.
The Time Thief is one of those gems.

It’s sharp, deeply moving, and genuinely hard to put down. The kind of book that sneaks up on you and refuses to let go.

Simon Jones masterfully combines rigorous science with human stories, exposing the broken promise of our buildings and the fight for the air we breathe. If you care about indoor air pollution, sick buildings, or how we’ve been quietly losing years of healthy life, this book is essential reading.

Highly recommended.

What are your favorite books on air quality?
I’m always looking for more good recommendations!

Starvind Box Silverstone

 Very simple & lightweight build. 

Frame wrapped in aluminum foil

Silverstone 184 iPro + Noctua NA-FC1 + Starvind filter.

 Dimensions : 11.5 × 3.75 × 15 in → 647 cubic inch

 Preliminary estimation  

- ~39 dBA low speed  gross estimation in a 35 dba background

- Est. PM1 CADR ~54 CFM

 Can run on battery, easy to take on the go.

 Sound (iPhone recording): https://www.youtube.com/shorts/-zzXn9MltZE 

(Note: sounds a bit different in real life)

 

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:

• Silverstone 184i PRO: 9.5/10
• Arctic P14 Max: 9.2/10
• Noctua NF-A12x25 G2 PWM: 8.7/10
• Noctua iPPC 3000 & Cooler Master SickleFlow 120: 8.5/10
• Arctic P14 Pro PST: 8.2/10

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