Saving the sounds of Notre Dame

How are we rebuilding Notre Dame to sound the same as it did before the fire?
Check out the full-VR ghost choir at: • Ghost Orchestra Projec...
Huge thanks to Prof. Brian Katz and Dr. David Poirier-Quinot for helping to make this video possible.
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This video was brought to you by an unhealthy amount of coffee and our awesome Patrons at / atomicfrontier .
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Hi, I'm James. I explore the world looking for interesting engineering stories which explore complex issues in interesting ways. I hold a First-Class Honors in Mechanical Engineering from the University of Western Australia and am currently studying a Masters of Space Systems Engineering at the Massachusetts Institute of Technology.
My website is www.atomicfron..., I occasionally tweet from / atomicfrontiers , and you can join the Atomic Frontier Discord server to talk about cool engineering stuff at / discord . You can help support my work and see some cool behind-the-scenes content at / atomicfrontier .

[@jameshorn3707]

Jim don’t sell yourself short, your musical talent is at least a sack of onions

[@t.wcharles2171]

No no that just doesn't do him justice it's a sack of shallots for sure.

[@ketsuekikumori9145]

Peeling back the layers, huh?

[@Palitato]

Cause when you listen it makes you cry? xD

[@Arwyroe]

@@t.wcharles2171 Hope he says thankshallot

[@LifeIsGoodMusic]

I bet he'd measure the reverb on them layer veggies

[@AtomicFrontier]

A much anticipated return to the "Engineering Europe" origins of this channel. This time with 90% more balloons

[@ommsterlitz1805]

0:00 If you where shouting like that in the real Notre-Dame Cathedral you would go to jail i think lmao

[@dkaloger5720]

And 100% more popped balloons

[@Kaynstein]

Just wanted to let you know, that you look absolutely dope in a pirate outfit!

[@DrBunnyMedicinal]

Oh? Does that mean you have an upcoming video about the Montgolfier Brothers? *grin*

[@sirBrouwer]

@@ommsterlitz1805 that's because you are not allowed to be on a building site with out all the safety in check.

[@playgroundchooser]

Another top notch video. I'm now incredibly passionate about something I didn't even know existed 10 minutes ago. Also, I still can't believe how perfect your one shots are... just another level!

[@gownerjones]

When you say you didn't know it existed, you didn't mean the Notre-Dame right?

[@MatHanley]

On the list of things I wasn't expecting to see today: James in a bath

[@AtomicFrontier]

As soon as I wrote that scene I knew we'd need a shot of me fully clothed in a bathtub. I don't own bubble bath so its actually dish soap.....

[@MatHanley]

@@AtomicFrontier I think that's what made it more absurd 😂 it would have still been funny but perhaps less weird. Dish soap is better for keeping bubbles around anyway

[@Lumynex8335]

wow your videos are great! you can just explain every topic you want and it always comes across like you are a professional who has studied this for years. thanks for your videos, and for explaining the world to others!

[@AtomicFrontier]

Thanks! The secret is spending weeks working with the actual professionals (and their papers) to make it as good as possible. Takes a while to make, but I'm glad you enjoy the results!

[@error200http]

Amazing. 3 years of telecommunications (signal processing) university classes summed up in 12 minutes.

[@timofei5771]

Documentary-level stuff. I remain completely unfazed

[@paperclipman123]

Did somebody clone Tom Scott without telling us? Great video man. The future of an educational and sane KZbin relies on people like you doing this work.

[@leonbraa898]

Love Your videos

[@CaiGwatkin]

Your narration style is musical to my ears! I remember watching an interesting video from your channel some time ago. The topic was interesting and the info you shared was great, but I notice now how much your narration style has improved. Lots of variation in your pitch and emphasis that really adds a lot to how the information is understood. Love it!

[@JuliusUnique]

2:02 human creativity truly has no limits... it's a great reminder for me to be thankful to live in a time in which we have more knowledge which helps us to be more in line with reality

[@JAKASHA420]

One of my brothers bought a church with his girlfriend, with a Casavant 656 pipe organ that is still working. It sounds awesome. The church has been converted to an art gallery for Dawn Oman and a sound stage and recording studio and an Air-B and B. My brother Scott is a master carpenter.

[@benmcreynolds8581]

Somewhat along the line of "mapping a structure" type stuff. I recommend looking into these Laser artists in the UK who use buildings to create software programed fast scanning lasers that play off of the architecture. It's really interesting.

[@UnspokenChicxulub]

It's so weird to see this person in places I regularly pass in real life, like line 10

[@AtomicFrontier]

So pleased! I come from Perth (where no one ever visits) so a big motivator for me was getting to show places where I lived to other people. I always love it when I get to do the same for others. What was super weird was seeing my university in the latest Marvel movie... I eat my lunch there!

[@Flashv28]

Hey, i see the thumbnail changed twice since the release & this vid doesnt get the views. Contrary to that I really liked this episode, the timelapses, CAD simulations and on Location shots are great, also the animations and reverb curves. Thanks for the awesome content!

[@maxz8807]

Absolutely amazing!!

[@maxz8807]

4:59 ah yes, the holy sponge

[@Ozblu3y]

you make great vids :) probably my fav youtuber and i've seen a lot of different people !

[@simonmikkelsen]

Great video, keep up the great work!

[@Agnes.Nutter]

sound convolution is so cool!

[@NikHYTWP]

Damn, cool to see that it's happening at my University. Granted, it looks like you were there during the summer before I started at SU but still cool that you visited haha

[@Onio_Saiyan]

File the whole "simulating reverb in a computer" under things I didn't know people can and could do.

[@Nirad-jt7en]

I love the Monty Python reference!

[@lilsnasne8712]

Your channel ist a goldmine man

[@sudonim7552]

5:23 AMOGUS

[@ronrozen2105]

Really interesting! Thanks, learned quite a bit :)

[@frostbird3431]

That's a cool pirate costume

[@hofmannwaves1525]

00:18 that's not the Sorbonne that's Jussieu

[@jeralwood6290]

good video

[@gmangmn5945]

so surreal that the only way to hear what its like in the old one is simulated, like a digitized ghost

[@fredericmazoit1441]

Oups, he did it again. Last time, he made a french man want to try American cheese. Now he taught this same french man that work was done to restore the acoustic of Notre Dame. He should really be ashamed of himself... or maybe not.

[@kautzz]

damn that's an interesting one.

[@Soul-Burn]

Cult of the Lamb!

[@elijahbutterfield4869]

A fire? Just a fire? Bro, wasn't it an act of terrorism?

[@coolcoolercoolest212]

Bummer about the ad 😬

[@Keovar]

4:28 - Obsidian* and Wool, nice. *Which the Minecraft version really can't be, considering how glasslike it isn't. I've had someone argue over this, in apparent denial that their favorite game is geologically inaccurate. Nevermind the flat world and floating rocks, I guess.

[@brick6347]

Both the cathedrals in my city are pretty ancient, and have wonderful acoustics. There's a more modern church in the suburbs that sounds like the inside of a supermarket. the 70s brought us great music, films, computers... But atrocious architecture!

[@petergerdes1094]

Who cares if it sounds the same? Just make it sound good!

[@mrbeancanman]

you deserve more viewers.

[@thirtysixnanoseconds1086]

are you a fan of James Burke old BBC documentaries? enjoy your videos!

[@AtomicFrontier]

I was actually introduced to him through some comments on my videos asking exactly that! And yes!!! He's brilliant. I'd love to do something similar with my own 30 minute TV show in the future.

[@jorgecarrillo2]

This is how Notre Dame Sounded when full of Catholics Chanting kzbin.info/www/bejne/m3e7dIeLo7VgatE

[@cwaldrip]

Blood sacrifice… ROFLOL!

[@jean-jacques5101]

You should learn how to pronounce French words and names, especially iconic places like Montmaete and St-Denis. Otherwise quite interesting. Many thanks.

[@sephreed1938]

Might want to look up the origin of the term "Jerry Rigged." Could save you some trouble later in life.

[@f__kyoudegenerates]

At tax payer expense no doubt.

[@sonkeschluter3654]

The private donations are close to 1 billion. If they keep the organization honest it should be enough

[@f__kyoudegenerates]

@@sonkeschluter3654 That's good. Better than using stolen currency.

[@danielhale1]

I'm really glad I followed your channel after the cameo on Tom Scott's. It's been absolutely worth it and you deserve vastly more subscribers. Thank you for the awesome work!

[@Martial-Mat]

Agreed, and now taht Tom is stepping down, this channels seems like a perfect successor.

[@MiguelAbd]

2:42 omg the courage to pop a balloon in a silent metro station haha

[@zperk13]

person in the background was surprised lol

[@jeremysmith7176]

6:20 One small note on Catholic terminology. A cathedral is the church where the bishop of the diocese has his seat. So there is only one cathedral in a diocese at a given time. A basilica is any church recognized for it importance and given the title of basilica.

[@sheikchilli8670]

"this doesn't sound quite right, we need to go find some bits of wood in the holy land to put in here" - sound engineers probably

Very much enjoyed hosting James for this piece in Paris on Notre-Dame.

[@BrassWing]

5:30 YOU'VE GOT TO BE KIDDING ME, DON'T YOU DARE THINK I DON'T SEE IT

[@doggonemess1]

I never know what the next episode is going to be about, and that makes your videos even more fun. Keep up the good work!

[@AtomicFrontier]

Glad you like it! And yup, eclectic is probably the best way of describing the channel :)

[@piraterubberduck6056]

Computer acoustic simulations are cool, but real life scale model simulations are pretty cool too. By using a scale model, made of materials with scaled properties, and by playing scaled sound (adjusted to a much higher pitch), which is then then picked up by microphones after reverberation, and converted back to its original pitch, you get a reasonably accurate simulation of the real space.

[@AtomicFrontier]

Yes! I actually filmed a scene about that but had to cut it for time. So cool!!

For information, we have used scale models to study some aspects of the cathedral's acoustics, specifically the column forms (see A. Weber and B. F. G. Katz, “Sound scattering by the Gothic piers and columns of the Cathédrale Notre-Dame de Paris,” Acoustics, vol. 4, pp. 679-703, 2022, doi:10.3390/acoustics4030041). However, a scale model of the full cathedral at any useful scale would be rather difficult to manage...

[@RENO_K]

Interesting topic and incredible presentation as always!

[@olimpiacookiethrower]

Every video surpasses the previous one. Keep on growing, be free with your creativity and joy of explaining different random topics, I for one am loving it all

[@Gear-Logic]

Wow, that's incredible. Would you happen to know the name of the simulation program they used? I would be very interested in looking into it.

[@AtomicFrontier]

CATT-Acoustic (www.catt.se/) but COMSOL is also pretty good (www.comsol.com/release/5.4/acoustics-module) and have some trial licences

[@Gear-Logic]

Thank you very much!

For information, we use CATT-Acoustic/TUCT for acoustic simulations. It is a geometrical acoustics software employing raytracing. You can see a bit more about making accurate simulations here (B. N. Postma and B. F. G. Katz, “Perceptive and objective evaluation of calibrated room acoustic simulation auralizations,” J Acoust Soc Am, vol. 140, pp. 4326-4337, Dec. 2016, doi:10.1121/1.4971422).

[@jaredvv86]

I am curious about the age of the wood used in the pre fire cathedral and how it effected the sound. The post fire wood will probably be significantly younger when it was cut so I wonder how that will factor in to the sound of the space

[@AtomicFrontier]

Yup! 100% The key factor are moisture content (the origionals had been drying out for centuaries) as well as the fact there aren't any old-growth forests in Europe available.

For information, the general questions about the wood structure deal with the roof, which is above the vaulted stone ceilings, so they have very little effect on the acoustics of the main cathedral space. Of course, the acoustics of the attic where the wood/roof is would be affected.

[@francinesicard464]

Oak wood has been used for centuries all over Europe for building boats, and it was these same carpenters who built the framework of cathedrals and churches, which is why all cathedral frameworks look like an overturned boat hull. The oak framework of Notre Dame, also called "the forest", dates back to the 13th century. More than 1500 oak trees, all of them between 200 and 300 years old, had been felled, with beams 100m long by 13m wide in the nave, 40m in the transept and 10m high. Before use, the woods had to be left to dry for sometimes 10 to 20 years. Before its collapse in 2019, it was one of the oldest structures in Paris. The craftsmen of that time knew their wood. The construction of these cathedrals required a great deal of planning, without forgetting that the craftsmen did not have, like us now, so many tools. The cutting stones and the beams could take several years, the reason why the work of Notre Dame began in 1163 and ended in 1345. The Gothic style was just beginning. Later, other cathedrals were built faster.

[@FOUNDERZERO]

The vibe of your work reminds me of something I could totally find on PBS. Keep it up!

[@illiiilli24601]

stuff i didn't know i wanted to know

[@planespeaking]

I bet everyone loved you in the underground station

[@plazmaguy13yago9]

5:27 AMONGUS

[@openperspective]

I'm halfway through this and i feel like the point of the video is... to make someone write a new "national treasure" movie involving the right acoustics to reveal a new Da Vinci Code

[@timeimp]

This is crazy - it’s something you don’t think about but BAM - architecture 🤝 acoustics

[@rolflandale2565]

Being able to replicate an entire environment that never chanced in history, is astonishing as time traveling and rewitting history literally.

[@MeanBeanComedy]

I swear to god, if they "repair" the cathedral and make it look like modern garbage, I'll lose my mind.

[@catva]

I was wondering when you'd show up in my notifications

[@joanbennettnyc]

"Lord Pi Rate" ... ... ... ouch ... ... ... ;)

[@TheWebstaff]

Change the thumbnail.

[@katherinekinnaird4408]

Great channel thank you from Bakersfield California USA

[@THarSul]

when i was a kid, i wondered if software like this existed, stuff that let us simulate the acoustic profile of different structures and locations, cause it seemed like a cool way to give sound an extra layer of depth, by setting it in a specific place, and i am pleased to see that the real world has finally caught up with my rambunctious imagination.

[@Ivan.Wright]

That jet at the start was crazy

[@dibenp]

0:45 Paying for a perfectly timed jet flyby?!? That’s serious dedication to the craft.

[@1.4142]

A cool experiment with sound is that you can use parabolic reflectors to communicated across the room like radar.

[@morgan0]

when capturing reverb of real spaces, you can’t get good results with an impulse without either clipping the mic (which no longer accurately captures the reverb) or getting noise by using a quieter impulse. the better way is to sweep the entire audible spectrum over some time, since a perfect impulse contains all frequencies equally. you can do it for longer times to get better results or shorter to capture in less time, and you could theoretically run many sweeps and average over them to get better results in a noisy place (but i’m not aware of anyone doing this). then in software you convolve it with a time inverted copy of the same sweep to get an impulse, and then convolve that with audio to apply that reverb. another advantage of sine sweeps is that any distortion will be moved before the impulse with the first convolution, and can be edited out. this distortion isolation is improved with longer sweeps.

[@AtomicFrontier]

Yes! That's actually one of the big tests they did with the cathedral, although it's a bit more recent a development so there isn't the historical data to fall back on. Plus as a demo popping a big red balloon is much more fun!

[@morgan0]

@@AtomicFrontier yea something viewers can immediately hear is gonna be way more interesting in a video

For information, the sine sweep method is what we regularly use. The balloon burst/gun-shot/impulse are included int he procedure as a fall-back situation if there are any problems/issues with the measurements. We were also fortunate to uncover some older recordings of measurements at Notre-Dame from the 1980's, and the only usable data were the balloon bursts (see B. F. G. Katz and A. Weber, “An acoustic survey of the Cathédrale Notre-Dame de Paris before and after the fire of 2019,” Acoustics, vol. 2, pp. 791-802, Nov. 2020, doi:10.3390/acoustics2040044).

[@luisdanielmesa]

I had subscribed 5 videos ago, in the afternoon. Once I saw the scam ads I just had to unsubscribe. Why do these KZbinrs sell themselves to these fraudsters? SMH

[@ba-a-a]

You gotta love multiculti, a gift that keeps on giving ♥

[@malcolm_in_the_middle]

Giving us burned down ancient cathedrals?

[@melody3741]

I sincerely dount its the shape most likely is materials being softer and absorbing sound

[@laurispeterisvejs4007]

Really high production quality! Amazing content!!

[@NamelesshunterGaming]

what would the holy hand grenade sound like in there? ... oh wait so that's how the fire started :P

[@JackAllpikeMusic]

10:50 not the transperth seat pattern 😭😭

[@_maxgray]

I was horrified when you popped the balloon inside the station - but I guess in places other than the US, loud popping bangs don't make people immediately worry someone is shooting.

[@daexion]

Loud, sudden noises generally cause people to suddenly become more alert and has little to do with guns, it's basic survival instinct. It's says more if people are used to such a noise and don't react than if people aren't and do react.

[@_maxgray]

@@daexion There's a difference between people "become more alert" and "literally stampede when they hear sounds they mistake for gunfire." The latter happens tragically often in the US. And it's not like the fear is unfounded.

[@Statusinator]

It's France, they have a massacre shooting there every week, inbetween the riots.

[@carpenterhillstudios8327]

Interesting thesis.Thanks for making the video and sharing it. Here's a question though. There is a prominent instrument in Notre Dame that remains uinmentioned in your analysis. It is the organ on the west wall. From recordings pre-fire there is a sense of what the organ sounds like in that space. The question: Will; you compare the organ sounds pre-and post fire? My point in asking is, theb organ and its subsequent renovations address the issue of sound in the cathedral space directly. Every pipe is literally adjusted to how it speaks into the acoustic space of the cathedral.

[@catorilana]

BROTHER MAYNARD!! Bring up the holy hand grenade!!!

[@oganvildevil]

Love Tom Scott but this guy is one of those dollar store knock offs that's low-key raising the bar on the original. And the shots and interviews he gets without a ton of tuber connections and resources speaks volumes.

[@michaellyons810]

your videos feel like a new version of James Burke's Connections

[@RossParker1877]

What a fantastic video. Thank you James

[@LanArchy42]

Always a good day when AF uploads

[@guesswho2778]

why am i only seeing this now? ive got notifications for this channel set to all.

[@aze4308]

imagine you get hired to pop a balloon

[@ItsDaCreeper]

5:22 is looking kinda sus 🤨

[@wesleyp3024]

who cares what it sounds like.

[@Ozblu3y]

blood sacrifice

[@pegasustargaryen]

I like that you illustrate the different hardness of materials with Minecraft obsidian, a tool your audience understands!

[@kenjackson5685]

1st class...

[@General12th]

Hi James!

[@thomilo44]

Damn, how'd you manage to be at Montmartre with so few people around?

[@AtomicFrontier]

Waking up far too early :(

[@KeppyKep]

Amazing video James. Fascinating how much different objects and materials affect the reverb in different ways. Something I was always vaguely aware of, but you made it so clear and explained it so well.

[@Carhill]

Absolutely love your content mate. The production quality and presentation are next level. I just wished to point out, and it may just be my end, but ironic to the topic at hand, it felt like the audio levels for you speaking differed noticeably throughout the video. I just thought I'd mention it as feedback. Have a lovely week. :)

[@hebl47]

I wonder if the patterns and colours in stained windows noticeably affect the reverb patterns.

[@FinnBassFo]

Incredible explanation og how acoustics work! We had literally weeks of classes in my university to just round up what you explained in 12 minutes!