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Contra Wirecutter on the IKEA air purifier

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Re: Contra Wirecutter on the IKEA air purifier

#671

Post by amluto »

etchalon wrote: post #574
amluto wrote: post #538

Earlier quoted context omitted.

Sorry, you’re still missing the point. If you are taking air, running it once through a filter, and using the air that comes out for an application that needs very few particles, then a 99.99% filter is “10x” as efficient as a 99.9% filter in the sense that the air coming out will have 1/10 as many particles. For example, a 99% efficient face mask is “10x” as efficient as a 90% efficient mask (assuming both fit perfe…

I understand the point. The point doesn't matter. Air purifiers operate on a fraction of available air. That air supply is continually being cycled, refreshed and mixed. Particulate matter within that air is not evenly dispersed. That, for a single minute, as a percentage of total air, a 99.5% and a 99.95% purifier produce a minor difference in total air quality is deeply irrelevant to the overall performance of the…

> That, for a single minute, as a percentage of total air, a 99.5% and a 99.95% purifier produce a minor difference in total air quality is deeply irrelevant to the overall performance of the purifier over any length of time. The 10x difference, however, will matter over time.

Can you explain, with actual math, what you’re trying to say?

There are plenty of plausible explanations for Wirecutter’s unexpected results. They could have messed up (quite likely). The difference in the behavior of the fans could be circulating the air differently (also seems reasonably likely). The conditions of the test could be such that the difference in CADR was relevant (possible but doesn’t seem likely). They could have failed to set up the IKEA filter correctly (I once failed to set up a Conway filter correctly — it was somewhat embarrassing). Or, by pure magic, the fact that the extremely clean outgoing air from the IKEA filter was less extremely clean than the extremely clean outgoing air from the other filter made a difference (seems very unlikely).

Re: Contra Wirecutter on the IKEA air purifier

#672

Post by OJFord »

> (Yeah, power usage goes down when you add the extra carbon filter to the IKEA purifier. I’ve confirmed this myself with a power meter. Physics is weird.)

Well it's not that weird is it? It went down because CADR went down, the airflow is lower so the motor's not 'pushing so hard'.

Re: Contra Wirecutter on the IKEA air purifier

#673

Post by amluto »

etchalon wrote: post #662
jefftk wrote: post #641

Earlier quoted context omitted.

> the original WireCutter article showed such stark differences between the performance of the Förnuftig and the Levoit Core 300, over a 30 minute span. If you were correct, over those 30 minutes, the amount of particulate in the test room would have been roughly equal for both purifiers. It wasn't. The Förnuftig removed only 64.5% of the particulate while the Levoit removed 97.4%. Note that you are talking about the…

We're talking about 0.3 micron measurements because the input value for his numbers is the efficiency of the filters in removing 0.3 micron particles (99.5 vs 99.95). The author claimed the difference between the purified air, as a percentage of total air volume, was small. He used percentages expressed as a decimal to make that difference look small (0.9005 vs 0.90005). But a clever observer would translate those nu…

Multiplying .9005 and .90005 by 10000 does not actually cause a 10x difference to appear. No, really, try it!

If your goal is to play with numbers, you could raise them both to a large power. You would discover that the ratio between them increases exponentially, but this would pale in comparison to the fact that both results would exponentially approach zero much faster than the ratio would increase.

Re: Contra Wirecutter on the IKEA air purifier

#674

Post by DubiousPusher »

simondotau wrote: post #612
baq wrote: post #609

Earlier quoted context omitted.

the choice is between having no negotiating power with HR or having some at the cost of being part of an organization.

If you're part of a union, you don't gain negotiating power, you trade away individual negotiating power for collective negotiating power. Sometimes this is a good trade. It depends on the context, on the industry, on the sort of work you do.

Yeah, just be one of .0001% of workers with a rare, highly marketable skill and you won't need a union...

Re: Contra Wirecutter on the IKEA air purifier

#675

Post by DubiousPusher »

mschuster91 wrote: post #600
simondotau wrote: post #580

Earlier quoted context omitted.

Which is great in theory, until you realise that unions can and do exploit workers too. Collectives of people (whether corporations, unions, or entire countries) tend towards corruption as they scale. History has shown that large unions are similarly prone to exploitation and corruption.

> History has shown that large unions are similarly prone to exploitation and corruption. Mostly in the US, it seems. Unions in Europe are healthy and effective. The key difference IMO is the interest people show in democracy and holding delegates accountable.

It's also somwehat moot. Unions in the U.S. get their workers better pay and better benefits pretty much regardless of corruption and did so even at the peak of their influence and corruption.

I think it's reasonable to argue against corruption but if you're argument against almost any human institution is just that it is corrupt, then you are arguing against the majority of human institutions ever. Which simply isn't practical.

Re: Contra Wirecutter on the IKEA air purifier

#676

Post by Shalomboy »

GekkePrutser wrote: post #626
Brakenshire wrote: post #176

Earlier quoted context omitted.

https://www.notebookcheck.net/ also seems to do a lot of their own testing.

Yeah they're great and in-depth and without the stupid showmanship of Linus. Just the info without the hot air :) Always the site I go for, wish they did more types of products. For screens I use displaycheck.

Hey, maybe the showman ship isn't for you, but what Linus and his Media Group have done is create the Top Gear of Enthusiast computer hardware. Tremendous entertainment value, exposure for niche sects of the culture, and an easy entry into the space for newcomers and young folks. That's gotta be good for something.

Re: Contra Wirecutter on the IKEA air purifier

#677

Post by azalin »

geerlingguy wrote: post #526
bityard wrote: post #309

Earlier quoted context omitted.

It's a myth that Phillips screws designed or intended to cam out at a certain torque. Not least of all because, the correct amount of torque varies wildly by application, even for the same fastener. I'll agree that Project Farm's videos can be a little formulaic and my least favorite thing about the presentation is that he shouts instead of talks. However, he's WAY ahead most YouTube tool reviewers because he does NO…

To that last point, that's why we have AvE and his BOLTR reviews.

BOLTR is ok if you take the review with a huge grain of salt, basically just as a proxy for having and disassembling the tool yourself. I largely disregard whatever AvE says and make my own conclusions from what is visually apparent. His standards for what makes a good tool are too focused on physical resilience - basically "if it can't survive being dropped into a mine shaft and beaten to hell, it's shit" is unrealistic for most people. Plus there's been reviews where he broke the tool during disassembly and reassembly and then blamed poor performance on the tool itself - the Ryobi Airstrike staplers come to mind.

This also goes to the other themes in the discussion here; there's few to no sources with singularly "good" reviews anymore, at best you have to synthesize from multiple reviewers and at times hope you can buy from a merchant with a good return policy.

Re: Contra Wirecutter on the IKEA air purifier

#678

Post by Mister_Snuggles »

highwaylights wrote: post #345
Mister_Snuggles wrote: post #291

Earlier quoted context omitted.

I'm not qualified at all to do a deep dive, but I've got a FORNUFTIG and a STARKVIND and can give you some thoughts. The STARKVIND is a LOT bigger than the FORNUFTIG. Assuming you're getting the standalone model, it's probably the depth of two or three FORNUFTIGs. This really surprised me. The table version is very interesting because it eliminates that problem by being a functional piece of furniture. The STARKVIND…

This is my use case more or less. Basically I want to be able to leave the house and say "hey google, clean this mess" and it'll start my strategically placed robot vacuums and run the filters on max while that's happening to minimise particulate spread. Mostly though, I just want some extra power for larger rooms.

I run my STARKVIND in Auto mode most of the time, but from 4PM to 9PM I have scheduled it (via Home Assistant) to run on full power - basically to clean the air, regardless of what the sensor tells it, before bedtime.

What you're asking for is 100% reasonable and easily achievable.

Re: Contra Wirecutter on the IKEA air purifier

#679

Post by k12sosse »

GekkePrutser wrote: post #670
sixothree wrote: post #666

Earlier quoted context omitted.

Got a link to DisplayCheck? I'm not finding what I think should be correct.

Sorry I remembered it wrong. It was DisplayMate, not DisplayCheck. https://www.displaymate.com/mobile.html#Latest Their display "shootouts" are unparallelled in my opinion. For example they look at colour accuracy not only at high brightness but also at really low brightness, where displays often 'cheat' by reducing the contrast when they reach the limit of their backlight dimming. Which significantly impacts colour…

Don't apologize for what you've said about the cult of Linus. Congrats to him for what he's built, but it's just not for us, and that's ok.

Thanks for linking DisplayMate, at first glance it's something I'll be needing to dive deeper into soon.

Re: Contra Wirecutter on the IKEA air purifier

#680

Post by saiya-jin »

ethbr0 wrote: post #226
bayindirh wrote: post #198

Earlier quoted context omitted.

There is also Rtings ( https://www.rtings.com ).

On the topic of displays, and specifically monitors, also the excellent TFT Central ( http://tftcentral.co.uk/ ).

another one - https://pcmonitors.info/

Run by one guy but he tests really well, bought my relatively cheap 32" few years ago and its great for both work and gaming with VRR.

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