Foam acoustics product that are not explicitly rated as being fire resistant have no purpose whatsoever in your studio, bedroom, basement, dog kennel, stored under your bed for a future project, or anywhere else. They are gasoline. Quite literally, they are made from petroleum.

Aside from the fact the only real absorption they offer is for every piece of dust, debris, strand of hair, and odor they come in contact with, they are extraordinarily flammable.

If you have not seen the videos of what happened in Bangkok this weekend, don't. It's absolutely horrifying. That fire has claimed the lives of 33 people so far, and in an instant there was a flashover that would've made you think there was a dragon breathing fire out of the main entrance into the street.

They are still investigating the initial cause of the fire, but in looking at the before and after photos, a few things are obvious:

1. In prior photos of the venue (shown above), every possible surface that could've had foam "treatments" did. Ceilings, walls, columns, and even the front of the bar.

2. In aftermath photos, the room and structure are in surprisingly good shape all things considered. It's almost exclusively the interior treatments and finishes that went up in flames.

3. If not for the abundance of highly flammable foam treatments and the associated toxic smoke, it's highly likely this incident would've been unremarkable with no injuries. Maybe refunded cover fees and a phone call to an electrician.

As to the acoustical performance of eggcrate-style foam products, if you were to crosscheck laboratory test data on the average eggcrate "acoustic" foam, you may notice it does very little for mid-band frequencies and nothing for low frequencies. Per unit of area, it's on average about half of the absorption of fabric-wrapped fiberglass panels. Meaning, while it's very cheap to cover a lot of area with -- you can get the same performance from fabric-wrapped panels while only purchasing half as much coverage.

If I sound a tad arrogant here, I can't apologize or be kind about this. This lesson has been learned time and time again with dozens of bodies per incident to show for it. Let us not forget the Station Nightclub Fire that claimed the lives of 100 people and maimed hundreds others. Same disclaimer applies -- if you have not seen the videos from the Station Nightclub Fire -- don't, unless you are the kind of person who after reading all of this is still thinking about buying or keeping unrated, highly flammable, highly toxic foam treatments.

If you must see the Station Nightclub Fire video as evidence though, here it is.

• The fire ignited from on-stage pyro at 0:20, quickly spreading across the foam panels they had used to treat the stage area.

• 30 seconds later, there was a crowd-crush toward the exits.

• 37 seconds after ignition, the fire alarms went off.

• 75 seconds after ignition, all you can hear is the fire alarm and blood-curdling screams.

• By 100 seconds after ignition -- under 2 minutes, there was a stack of bodies 4ft deep that people were trampling over to get out (not 4ft front-to-back...4ft floor to ceiling). Many who perished never made it near the door and got stuck in the bathrooms or other areas because of the thick, toxic smoke that the foam treatments generated. They couldn't see even 6 inches in front of them.

• By the time the fire trucks showed up roughly 5 minutes after ignition, it was all over. The building was engulfed.

So imagine that you have treated your spare bedroom with these products -- and for whatever reason they ignite while you are asleep. It is highly likely by the time you wake up that the fire has already spread and created blinding smoke throughout your entire residence. If you're lucky, there may still be time for you to stumble outside if the choking superheated smoke doesn't get you first, but the odds you will have time to save loved ones or pets is quite low. You will probably succumb to the smoke and superheated gasses first.

Friends don't let friends, or even enemies, use common unrated foam products as acoustic treatments.

Really wanted to buy some Acoustitape but unfortunately Genelec has discontinued it. I know there is probably a million other ways of more effectively measuring wavelengths but I have a friend who is a real sucker for this kind of studio accessories and wanted to gift him this.

Anyone know anyone selling one or anywhere you can buy them online?

Credit https://www.tiktok.com/t/ZTSEDX1Sm/

Bought a house with a concrete Racquet ball room. The echo is so overbearing I can’t stay in there to long with people.

How can I reduce the echo?

I'm the developer of amscan. I built it with Andy, who made amroc, the room mode calculator some of you may know.

I started this because every time I wanted to simulate a room that wasn't a rectangle, I spent hours in CAD fixing a mesh before I could run anything. So in 2023 I reached out to Andy, and we started working on it together.

You scan the room with the LiDAR on an iPhone or iPad Pro, set your listening position, and get a heat map of the simulated response from every point in the room, 20–200 Hz, with the frequency response for any point. You can place two sources and compare them.

Because the system is reciprocal, it also works the other way: put the marker where your sub is, and the map shows the best places to sit. So you can see a null at your seat before you move anything.

Underneath, the scan becomes a watertight, low-poly mesh in a few minutes, so L-shapes, alcoves, sloped ceilings and openings are part of the model, not a bounding box. The solve is FEM (openCFS). You can also export the mesh to continue in COMSOL, CHORAS or your own tools.

Limits: it's a simulation, not a measurement. Point sources, 20–200 Hz, two sources at a time, iOS with LiDAR only. So far one user compared it with REW's room sim and a sub crawl in his room and got matching results. That's one room, and I'd like better evidence.

Pricing: the app, scan and first 5 room modes are free. Placement is paid per listening position, one-time, no subscription or account.

It's a niche in a niche in a niche, and I've spent a ridiculous amount of time on it, perfecting every corner (with help from AI too). Andy and I made it the way we like software to be, but we built it in a vacuum, so I honestly don't know yet if it's useful to anyone but us. Our intention was to make a good starting point for acutual measurement. But at the same time, I’m afraid this was a complete waste of time. 

The Question: 
would something like this be useful to you, in your work or in your own room? And if not, what's missing, or why would you never trust a simulation for placement?

And if you think the whole approach is wrong, I want to hear that too. I'll be around to answer.

Link: AppStore

I was at a museum and was curious why this room sounded so good in spite of what appears to be a potential echo chamber. Then I felt under the table and found that the acoustic paneling was placed there. Super cool and surprisingly effective.

Back story: recently moved into a loft, which is great except for the insane echo. I knew I needed to dampen the space but I didn’t want to ruin the vibes. So I built a frame, stuffed it with Rockwool, and covered it with preserved moss. Built this smaller one to fit on one wall as a test before making some larger ones for the first reflection point on the back walls.

So this is mostly a furniture more than what it is supposed to do. I did see some differences when i tested the acoustics. The tip of a high in the low end got cut off:D This took me and my dad about a month or more to make. Due to not finding the right materials and such. But we made it!

I was commissioned recently to build sound panels for a studio in Brooklyn. 2 of which are these height-adjustable rolling gobos. I know I didn’t come up with the concept but I am excited about the design so thought that I would share!

If interested in seeing more of the build process you can on ig: @simeonbeardsley

I feel like this sub is 90% redditors asking for help on where to put acoustic panels or how to isolate sound in their house. As a practicing acoustic consultant and a Masters of Engineering in Acoustics student, I would love to see this sub blossom into a community that shares research, raises new questions, and encourages thoughtful discussion, rather than recycling the same questions over and over. Maybe we can pin some quality existing room acoustics and sound isolation threads in a FAQ to keep the new posts more unique instead of restating Acoustics 101 over and over.

Just my 2 cents. To attempt to lead by example, I am currently working on a environmental audio classification method using low-level features extracted from WAV files. My current step is to use fuzzy c-means clustering to predict the probability of classification for new WAV files.

EDIT:
I like the idea of using verified flair for actual acousticians in this sub.

I've been working on this for a few years, ever since releasing gostringsynth in 2022 (a FDTD synth you play from your terminal). It's all inspired by the work I did during my Masters in Acoustics and Music Tech at Edinburgh back in 2009. I work in biomedical engineering (ultrasonics) now but it's all pretty similar!

It's a VST/AU plugin for macOS, Windows and Linux, made with JUCE. You can download it free here: https://www.differentinstruments.com (and also see a nice slow-mo animation of the FDTD scheme on the website).

Thanks to everyone for feedback on my plan. It took me two days to complete (still needs painting) and it works surprisingly well!

This is designed to separate two areas of the house for very occasional renters / airbnb renting, so it needed to be removable.

Since putting it up we’ve had in-laws stay there with their very loud toddler and haven’t heard any of the screaming (until they all cone hang out on this side of the wall lol).

There is another door behind the wall separating the spaces but it has huge gaps and doesn’t block much sound in its own.

So the wall works!!

I used 3/4” MDF to sandwich about 1/2” of rock wool (see pics) inside a frame made from 1x2’s. I had to kind of peel the rock wool apart because it comes in pretty thick 3 or 4” panels, but it came apart easily.

The bottom of the wall has a few strips of adhesive felt to help seal it and allow it to slide on the floor when we’re moving it, and the sides and top are lined with weatherstripping.

Very happy with how it turned out, thanks again to everyone here!