No one: Absolutely no one: Dianna: So the other day, I was holding a tube and I thought to myself, "hey, I can find it's resonant frequency"

tube: exists Dianna: "let me sing into it to find its frequency"

as a musician, I can confirm: our job is indeed wiggle air in a pleasant manner

Every singer, classically trained ones especially, know this as the passaggio. It's the point at which this happens with your vocal tract, causing a change in muscular function in the larynx. In fact, many voice teachers encourage warming up while singing through a straw.

This reminds me of the nodal point on a drum. There’s certain points on them (usually the center) that you shouldn’t hit because the vibrations of the drum head start colliding with each other and canceling out, making the drum sound dull and lose lots of resonance. This is especially noticeable on a timpani because the drum head is so large and we’re use to its sound being sustained instead of just an percussive articulation.

This is a whole new definition of you-tubing. :)

I'd be interested to see what happens if you sweep through the natural frequency of the tube with a speaker.

I love this: singing through a trumpet is similar: you cann't sing certain notes, but you can if you use the valves (if you use the right ones to prolong the tube) could you as a physicist look into this/ Can you make a cool out of it (or maybe with a trombone?)

I remember doing this when I was a kid and finding the “crack” fascinating. Glad to see it explained.

Omg Alicia is a smaller but identical Dianna

I propose we call this "The Dianna Effect".

Basically you're experiencing a "standing wave" - at the point of resononance the pipe is going its going to have a maximum but at other frequencies there is a minimum - depends on the half-wave versus quater-wave. We have exactly the same affects when driving radio transmitters into antennas if the antenna does/does not match the radio frequency. In radio we refer to a "voltage standing wave".

I am a soprano singer and an aspiring physicist, and I found this so interesting! I (and I believe everyone else) have a couple spots in my range that are extremely difficult to sing without breaking, the only way I can explain it is it feels like flipping a switch - like something physically changed, but I can't tell what. Music and science are my passions, and I am so glad I found this explanation! I'm off to find a PVC pipe and try it myself!

This is how a bugle works, and if you have ever messed with a brass instrument you have experienced this.

This is so oddly predictable to a trombone player.

Im currently in Switzerland doing at the EPFL a master semester project on this specific problem. The problem that you faced is that the input impedance (average of pressure divided average of velocity) at the eigenfrequencies (there are always multiple because of the harmonics) is very very high and it makes for you impossible to put that pressure into the tube. If asked I’ll share here my research. :)

It was great to catch up on this older video after seeing the short. I hope Dianna recovers soon and can make videos again, but this deep catalog of videos can hold us over for a while longer.

How physicists come up with stuff to research: start playing with some tubes and singing into them until something weird happens

As someone who played trombone for many years, I experienced that moving the slide will change what note (frequency) this will happen at when singing into the trombone.

As a music teacher, physics geek/amateur, this was AMAZING. Love love love your videos. Thanks so much.

I know what happens when you try to sing through the resonant frequency of your vocal tract. Yodeling

So the tube screams back at you at its favorite frequency...?

I discovered the resonant frequency of my bathroom while singing in the shower as a kid. I had no idea what it was (until I studied music in college) but loved to sing that note because it made my head vibrate.

I recently found your channel...I love it! You have an enthusiasm and natural teaching ability that makes me want to come back to visit the rest of your content. Keep up the great work!

This reminds me of moving from full voice into falsetto; it's like stopping to "shift gears" in your voice!

I love this! Nobody ever seems to appreciate spontaneous curiosity. I ask these kinds of questions ALL THE TIME and people just look at me with what I've come to call "the blank stare" lol. This made me smile so big to watch, thanks so much for sharing!!

As singers learn to sing, they need to train themselves to avoid places where the resident frequency causes certain notes to be difficult to sing. There are places where they have to change which resodent chamber in their body they are using, such as their chest, throat, or sinuses. Their voice will "crack" at certain notes. I don't know if this is the same phenomenon as you noticed, but I wouldn't be surprised.

So glad I found this channel, you're really good at explaining things!! :)

"Something NOTABLE about natural frequencies" missed pun opportunity

Immediately paused video, ran out to garage and tried all the different pipes I had. So cool Dianna!

The straight bore flute, tapered bore piccolo, narrow middle bore clarinet, flared bore saxophone all capitalize on this acoustic impedance for their respective timbres. Thanks for laying out all the parameters and references, so we can experiment with our vocal and mechanical transducers!

Thank you so much for uploading this video. It is helping me get through the pandemic!

As a musician and physicist who has already learned plenty about the music-physics relations, the opera singer fact blew my mind. It explains why they are able to sing so powerfully

I'm both training in school as a physics major and outside as an opera singer, and I have ALWAYS wondered about this exact thing ! Opera singers are able to project their voices over orchestras of sometimes 100+ instruments, and the training in opera can really be boiled down to being able to consciously change the shape of the mouth and throat, and how to support this change with breath. I always had a suspicion the incredible resonance produced had to do with possibly resonating frequencies in the bones of the face, but being able to change the resonant frequencies of the actual muscles makes much, much more sense. thanks for answering this question I've been thinking about !

Love these. Old-school speaker design used cylindrical ‘ports’ to help boost/cut certain bass frequencies. Acoustic engineers understand the back-pressure well (call it ‘impedance’), and either avoid or use to their advantage to ‘tune’ a cabinet. Similarly, on the singer-side: check out the “Tenor’s Formant”… just like you mentioned regarding sopranos pitch-tuning, tenor voice box can access a particular range of frequencies where the sound resonates *very* loudly (for very little vocal effort or air). Seems that only Tenors (and some sopranos) have the resonance, which seems particular to resonance between their folds’ particular aspect ratio and human hearing.

I love that you find these weird physics problems in every day life! Everyone sings into tubes as a part of every day life, right? :)

You mix the experimentalist side of physics with public education really well. I really like the videos you make. This is one of the gems. I also experiment with finding the resonant frequency of things in just the manner you used, though I've never tried it with a tube. That result is nifty and surprising.

Congratz on your wedding, please keep doing what you do! I love your vids.

I had to try this with a one-inch internal diameter 15-inch long piece of PVC pipe I found in my garage. Amazing! The sound broke down repeatedly at the same frequency every time. Love your videos, Physics Girl. Keep them coming.

Don't stop being pedantic. It's one of the reasons I like your videos.

It seems to me that what is happening is this: When you hit the resonant frequency of the tube, it sets up a standing wave which dramatically changes the impedance of the tube, making it more difficult to sing through. I want to see the following experiment: First, record the actual frequency of the notes above and below the "cracking" effect. Next, choose a frequency between those, and sing it. Finally, while singing this magic note, bring the tube up to your mouth and see if you can either power through it, or if it causes your note to shift.

Great video! Thank you so much, very intriguing information!

thanks for this video! i had experienced resonance by accident when playing the guitar.. but you just provided an easy to understand explanation for the immense forces behind that!

Clearly your musician friends aren't brass players. As a Trombonist, I recognized this "phenomenon" as the harmonic series.

Isn't this the entire idea behind brass instruments?

Fascinating. Just a few weeks ago, I noticed that there were certain notes I would sing in my shower that would resonate more than others, that literally "felt" like they filled the entire space. I figured it had something to do with frequencies, but I never really extrapolated that this might apply to all sorts of things, or that it was the same as blowing/whistling across a bottle. Awesome video!

Love love love this! One of my students shared this video with me and now I MUST try. I'm a soprano, so I;m curious to see how I can manipulate the sound!

I can’t believe I finally know why this happens!!! I play in band and I do this into my trombone. It does the same exact thing

You just solved a huge mystery I have been having in my singing career. When I get kind of congested in my throat, sometimes I have the issue where I can't sing a certain note and my voice skips just like you with the tube. Now I know that all the stuff from my allergies must be changing the resonant frequency of my throat and therefore not allowing me to sing at that frequency. This is MINDBLOWING to me.

Love you channel & clear explainations of complex things. Thx. Also - your overdub edit at 4:40 reminds me of the Wizard of Oz when the Scarecrow suddenly explains the Pythagorean Theorem. Inadvertent humor bonus!

This was awesome. Could we have more on frequency and singing, music.. In training we called this 'tuning', overtones and undertones, extra sounds (vibrato). throat singers are masters at this and opera singers

Something interesting I noticed: The space of the notes between the skip was always a minor third, except with Derek, who skipped a second.

This is fantastic! I teach audio engineering, and it's hard to find good video content that explains resonance and other audio-related phenomena. Thanks!

As a classically trained Bass , as well as a classically trained clarinetist... I was aware of this and am impressed at how easily you grasped and then explained a concept that took me ages to understand. This is the video that convinced me to subscribe to your channel. You rock!

Loving your videos!!! 😎

I am definitely going to be having people try this with no context. Thanks diana!

I get so ridiculously excited when I see there's a new video up from you! Your enthusiasm is contagious!

YES!!!! I've noticed this for years!!!! Finally an explanation :-) THANK YOU!!!

hadn't seen this one before, but was happy to watch after seeing the KZfaq short

Completely random 3blue1brown face reveal, lol.

Hi! My husband just showed me this video as it intersects with our interests. I studied voice in college and singers are taught to sing through our break, which is a "break" in sound where it cracks like the note in the tube does. It's well known among vocalists that singers all have unique notes where their breaks are. For many female vocalists it's somewhere between an e and f, if I remember correctly (don't quote that😬,) but still varied among singers. I'm assuming that's due to our differing shapes in (maybe?) the trachea (or other section of the throat.) Anyways, we tested this with a paper tube and I mostly sing through the "break" in the tube. It doesn't stop the sound, but I can physically feel my throat changing shape to accommodate for it. It's also interesting because I didn't know where the break would be, but I naturally anticipated it. It's harder for me to find the break. It feels like rewiring an unconscious habit. I have to be careful not to change my mouth shape at all to make the break happen. It's fascinating! I'm by no means a great vocalists, but I was excited to test it out and see how it went!

You absolutely right. Phase is so important. All my Audio Mixers have "Phase" reverse switches on Mic inputs. A five position switch was added to Fender Stratocaster's to connect 2 pickups together out of phase. Then you get the "Eric Clapton Sound" and you hear how much more bass and full sound with the 1-3-5 settings on the switch opposed to "Out of phase" settings 2-4 with a pair out of phase. Out of phase settings 2-4 with a pair of pickups then cancels "noise". Les Paul put two guitar pickups in phase with a nickel chrome cover and this cured the ever changing hi-impedance noise. Hence the first Gibson Patent Applied For Humbucking Guitar in 1957. All Guitar players still play with these pickups today.

Wow! Professor Wolfe. I'm an absolute fan of him

0:40 3blues1brown I never miss his videos.

MAN, that is cool! I love how you stumbled upon this random phenomenon and then found just the right scientist to explain it. And it just makes so much sense with resonant frequency and phase, but i'd have never guessed it!

Back in college, in my voice class, we learned about and studied this kind of stuff. In vocal lingo, the point where two types of voice meet is called your break. The scoop sound in the tube is kind of what it sounds like when you're practicing. You will hear voices having trouble singing a note or two near their personal break. Often times, we learn to control the break with added tension on our voice. This is what ultimately gave vocal cord issues with singers like Jordan Sparks or Adele, and also explains the mess up Idina Menzel had on New Years Eve (Not to single out ladies, it's just what I remember off the top of my head). My voice teacher (Dr. Mary Logan Hastings) had me go through a tension detox, and literally, when you truly relax your vocal cords, your pitch goes out of control, but if you bring the tension back and try to control it, it's like putting your feet down when learning to ride a bike. You need to just keep the breath moving, and let whatever comes out come out, and eventually you will learn how to ride along with it. I spent that semester locking myself in the soundproof practice rooms singing scales and sounding like a tone-deaf yodeler, and after a few weeks of that, suddenly I had a real good handle on my voice. It was amazing. I have since gone on to teach instrumental music, and when I sing, it's loaded with the same tension I had before I took the voice class. So, from a musical standpoint, I see you extending a critical part of your vocal tract. If you want to try singing scales daily into the tube, you might get better at it in a few weeks.

Absolute enjoyment watching Dianna regardless of her topic. She brings such energy to understanding the world around us that we are enriched by her knowledge and enthusiasm. May she continue to regain energy and strength during her recovery and that we should always and only send love and energy to her!

It's 4 am and now I want to stick a pipe in my mouth to try this thing... What is wrong with me?

Sounds a lot like the harmonic series is involved too. If you buzz your lips into the pipe, the different pitches you can play are part of the harmonic series. That's the entire idea behind brass instruments. Singing into it is really just like buzzing except it's your vocal cords instead of your lips doing the vibrating. As a musician I know a lot about the application and how it works less about the why it works because I'm not actually a physicist.

I've heard a lot of voice teachers on youtube explain how resonance in the throat works in relation to singing but i didnt really understand it, but listening to your explanation from a physics perspective I finally understood. I think it's because music theory and professions that study it have their own terminology to explain things at a level that is practical for their field but I can't relate to, whereas using physics terminology I actually did learn in school seems like a deeper level of understanding of the same concept and at the same time ironically more accessible to my understanding it.

I've been making weird sounds in tubes my whole life, making my dogs look at me, heads tilted. I never once considered that I was changing phase every time by voice cracked. I sing, play guitar, drums, some brass, etc. I record and produce music, acutely familiar with getting all of the sounds "in phase" Totally blind to this, the ENTIRE TIME! I've done a lot of tube singing too. Yes, I am too easily entertained. So, in my oblivious studies of practical phase shifting applications, I have learned that a longer tube produces a more dramatic phase switch. A wider tube causes a phase switch at a higher note. Tube materials have an effect on how the phase changes as well. All of these facts I've ascertained without putting 2 and 2 together... 🤦‍♂️

I love it that I was about to ask a question (about the resonance of the vocal tract) and you already answered it!

I thought this said "signing this note is impossible " I thought we had some magic ink.. I'm sad

love your videos please get well soon I want more.The world misses you .

I'm so happy I found this corner of the internet. I'd love to see a Physics Girl/Charismatic Voice team up!

Also I'd love to see you cover Overtone singing!! It's something fun anyone can try and falls under the whole resonating frequency topic!

1:00 that one kid in your class that does this everytime someone gets in trouble

This is crazy! I was actually doing this yesterday! This happened inside different types of tubes too. I was wondering about it but never got to asking people. Thanks for the cool video!

Very interesting as usual!

That's an interesting experiment...A lot of this type of work about back-pressure and resonance will have been done over the years in the development of 'expansion chamber' style exhausts for two-stroke motors. :)

Thanks for the great video! I used it in class today. I had some PVC, and we loved playing with the resonances and hearing the dying animal noises.

awesome ! so much knowledge packed in few entertaining minutes :D lovely! :D

This principle is used in speaker enclosures, in order to design bass reflex. When the frequency is above the frequency of the baffle (usually a tube of some length and diameter), the pressure is to high, so, the air cannot escape from this baffle and the response of the enclosure matches this of a "closed box enclosure". AT resonant frequency of the baffle, the sound gets amplified due to the resonance of the tube. It's like having a 2nd speaker that plays synchronously (stationary waves) the same frequency (Although, there is a slight delay of n cycles, so that's why the is a slight "reverb" effect at these frequencies). On a speaker that the the frequency of the incoming signal is usually a mix of frequencies, this results on a physical/mechanical "Bass Boost" (since, the specific frequency is amplified, and the rest work as mentioned above). On frequencies lower then the resonance point, the baffle works like an open hole, so the sound gets attenuated even more than when it gets played on a closed enclosure. So, the whole idea of a bass reflex is to be "tuned" right where the physical frequency response of the loudspeaker itself starts to "be less efficient". That results in a slightly better low-end response of the speaker-system than before.

I love how excited you are about all this🤣

This sounds exactly like a wolf howling and if you listen to a wolf, it's howl also misses a note or two. Is this the same reason for a wolf's voice?

THIS IS SO INTERESTING!!! A phenomenon, I never experienced but which is so interesting to know about. Also the fact that sopranos do the exact opposite. Now I know more. Thanks.

This is the most intriguing science video I have watched in, like...foreva!

I remember noticing this when I switched from woodwind to brass in grade school. With a brass mouth piece alone, I could adjust the vibration smoothly up and down, but as soon as I put the instrument to it (trumpet and French horn mostly), I was limited to the notes that were indicated by my fingering. I never followed up on this question tho. Thank you! lol

"Every soprano we ever measured... ... exploded like a wine glass." "It was very messy."

I discovered this while singing into my clarinet in like grade 8. It always kinda puzzled me but I didn’t put too much thought into it. Good video.

oh thank gods somebody made a video about this. ive known this back in the 90s. thanks!

Would've love to see you try this with Simone Giertz, I love watching the 2 of you together

Weird! I just discovered this last month while using a PVC pipe for a cheap didgeridoo option, and had no idea why this kept happening. Thank you for the awesome video explanation!

Fantastic comment below about passagio (Bravo, Asad, a year ago and still great). As a baritone, I have a good falsetto, and the "clickover" spot between my two "voices" or "phases" is inaudible if I have practiced and stayed on top of it. Without practice, the "click" comes back, and I haven't tried yet to see if the pipe will thwart my efforts to hide it. Mariachi singers do a wonderful deliberate "click" at full power to get that cool "Ah-ya-AAAAH". Now go sing the Phantom of the Opera's arias into a PVC pipe; science is fun.

I did my best siren voice and went thru the frequencies. I did the scales with and without the pipe. The pipe had these dead zones, like I had stopped singing, but I hadn't. I repeated without the pipe and the breaks were not there. COOL!!! Nice experiment. I loved all my physics classes we always got to play with toys in the labs. I had a physics teacher who was shooting a ball bearing thru a tube and dropping a second ball bearing from a magnet on the ceiling. Proving horizontal velocity is independent of gravity. That has been a very long time ago. He actually got the balls to collide. He was my favorite teacher in HS. You could ask him absolutely anything about any subject.

What would happen if you projected the frequency through the tube another way? Like a speaker fitted to it?

This is probably how brass instruments work! It is extremely difficult to bend a pitch up or down even a few cents (or hertz) without jumping to the next note in the instrument's overtone series. For instance, a trombone in first position jumps up from the fundamental B-flat to F, which is a perfect fifth interval (a 50% increase in frequency for you physicists). However, when the tube is shorter (i.e. just singing through your hand or buzzing through a mouthpiece), the resistance to hitting certain frequencies is minimal, so it's much easier to slide through the full range. It was nice to learn how it works! Thanks!

This was actually very cool to find the natural resonances of my didgeridoos! Great video!

It is the stretching of vocal cords that changes pitch not the throat wind pipe that only amplifies the note amplitue. Your throat muscles had full pitch control until you were linearly stretching them comfortably toward tube's resonance. At PVC tube's resonance frequency, however, you became a just a component of a larger externally resonating system which would then overpower your carefully increase of muscular stretch. Imagine at 440 Hz, you were singing "A". While approaching the vicinity of A, e.g. 1 Hz below -- there would be a beat frequency of one cycle per second thumping your vocal cord stretching system confusing the perfect neural control (not aware of external thumping) cracking your voice. An inaccurate but more intuitive way to describe would be by imagining that for some reason one of the prongs of tuning fork attempting to oscillate at a frequency slightly different than its physically/inertially entangled pair. It would experience the beat frequency and would experience massive resistance for trying to defeat the mutually agreed "resonance inertia" -- breaking the contract. The tiny muscles stretching your vocal cords with delicate neural control feedback control loop (involving your ear) are not match to overpower the energy of a very stable meter long external oscillating column of PVC tube. Perhaps it has larger, more stubborn momentum, and could easily crush the feedback control loop involving the tiny muscles at beat frequency! Have fun!

Hey Physics Girl! This was a really fun and interesting video. My follow up, would be to find perhaps a Choir or something similar with Vocalists to try this. Then also try to find a way to enable that mysterious note to be played through the pvc pipe as you were trying to. It seems like it could be a really fun collaborative video challenge to experiment with different methods and modifications such as with Veritasium and the likes. While singing, rocks, and stones were some of the earliest of instruments. Where would we be if no one explored the dynamic ranges of strings whether metal or gut? We didn't just get the piano or the violin by accident. Those dots getting connected have completely changed our world. Life with out Science, would be vastly saddening. So yay for Science!!!