Wild Fires, Air Purifiers and Sound Systems


The following is a question for western audiophiles.

The current wildfires have caused so much devastation. Yet we are seeing increasing numbers of summers where we are forced to stay indoors because of hazardous air quality from fires.

Lots of folks invest in cleaning up their power supplies and treating their listening rooms for the best sound possible. When we replaced our HVAC last year, we chose a system with passive filtration and active purification. That has done a remarkable job, but my listening room which goes directly outdoors still suffered from some smoke infiltration. So we need to purchase a portable additional unit, and I put in an order for one (back order, because everyone has same idea). What I didn’t consider was the frequency of the fans (not that one can find those specs easily). Since these work best when run continuously, the noise they produce is hard to avoid.

Does anyone have a brand of air purifier, which, while in operation, is least disruptive to the music?

This may seem an absurd and privileged question to ask when so much life is at stake. In one sense, it is; but like COVID-19, we westerners are all going to have to learn to live with these periodic conflagrations. We might as well have the healing power of music to help.
dramatictenor
The Coway Airmega is a great recommendation, I use its larger sibling the 400s in my listening room, its my endgame purifier and love it. Another great option I use in ever other room throughout the house is the Winix 5500, its comparable to the Coway 200m but can be had for a better price, looks great and whisper quite. Hope an end is sight for you and yours out that way!
@tablejockey , I don’t know why folks do what they do. But I suspect we have lost the training to think of others first. The rains have begun here, and while AQI is still triple digits, its under 200 which is a milestone here. 
@jameswei , thanks for a specific recommendation. I jow have a coupke of brands I can research. Appreciate it. 
I live in Arcadia and I bought a Coway Airmega 200M last week.

It has a HEPA filter and an ionizer, as well as an air quality sensor.

It is pretty quiet except when the fan is on high, and so far my asthma has not flared up.

It is rated for spaces of 360 square feet.  If your room is bigger, consider a larger model.
The nearest fires to me are in San Bernardino county. They are still not even 25% contained! Being on the coast, the air quality is just know "improving" with the index under triple digits.
I can't remember breathing/seeing it as bad as it is. 

Thanks to the idiot couple who felt the need to use fireworks in their dumb gender reveal party.
Why do parents need to stage "events" about everything in their lives these days?
Just this week I installed an Air Scrubber into the house-wide HVAC, as such it's no louder than the HVAC itself. I'm not sure it will completely fit your needs, as I bought it for a new puppy who turns out I'm allergic to, but worth checking out.
Thank you Steakster. This is a really useful endorsement. And your multiple purchases give me a sense of confidence. How wonderful to have devices to address asthma. I guess these fires have made us all a bit more sensitive to what it’s like to live with asthma on an ongoing basis. 
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My accoustic and electric engineer friends have told me only to use ferrite if I am hearing electrical noise. Given how clean my electricity is, I will keep this in mind but probably don’t need to. Of course I have not yet gotten a unit to deal with so let’s see what happens. 
If you put a motorized unit in the listening room the electrical noise might be as bad or worse than the acoustic noise. At least put ferrite clamps on its power cord

Living in an apartment built in the '70s, my option was to go for some Germguardian HEPA devices a couple of years ago. Just an hour ago, I had to order two more filters as the ones I have aren't doing as good a job as they used to.

Upon awakening, I can smell the ashes even though I have blackout curtains as well as vertical blinds and run the filters all day long during these fires. The smell goes away but taking a look at them shows they're at the end of their effectiveness. 

That, and there's now more dust on everything.

All the best,
Nonoise
Of course. I think I got the last Merv 13 in LA. :)

Regarding this DIY box fan, if I understand you correctly: duct tape a high quality filer to the back of the box fan, insuring all air must go through the filter. Then turn the fan on and let the MERV13+ do its thing. 

Yep.  The best Ideas I've seen use a V shaped configuration to double the surface area and air flow. 

I've used a lot of portable air filters, but the total air flow is limited, and yes, they are pretty noisy.
Oh, and of course all the stores are sold out of filters for the time being. I will be in great shape for the next fire, God help us all.
Hi Erik,

First, thanks. Yes, the furnace stuff is in good shape. The HCAC vented part of the home is smoke free and healthy. My listening room, on the other hand, used to be a covered patio. When we enclosed it, we didn't add HVAC because it frankly doesn't need it (a small electric heater in winter is enough for the 500 square feet), we couldn't extend the current system because of how house is set up,
and it would have been cost prohibitive to add a second system that again, wasn't really needed. 

So I am really asking if people have experience with portable units from a noise perspective. Regarding this DIY box fan, if I understand you correctly: duct tape a high quality filer to the back of the box fan, insuring all air must go through the filter. Then turn the fan on and let the MERV13+ do its thing. 

I wish I could attach a drawing to make sure I get this.

D
Hey OP,
I’ve had to do quite a bit of research onto this subject for the same reasons. A high quality furnace/AC filter which is rated to at least Merv 13/Filtrete MPR 1900 will filter out smoke very successfully. For the wood smoke we are suffering, based on the air quality reports around the LA area I have seen we need good PM2.5 as well as PM10 rating. Merv 13 starts to cover PM2.5 very well it, but Filtrete has a couple of filters in the Merv 13 range, higher MPR is better, and Merv 14 seems like it’s nearly HEPA from the stand point of wood smoke and the PM2.5.

For best results use higher rated filters. There’s a lot of work on DIY setups using box fans, duct tape and these high quality filters. The box fan setups have the advantage of being relatively quiet especially on low mode, inexpensive and they move a lot of air.

Best,
Erik