Interaural time difference and how to find your phone instantly

Dang it! Now I understand why I hear high pitch noises in wrong spots! Thanks for answering one of my sub-conscious questions!

So I was actually wearing headphones and still tilted my head around like the biggest idiot. Turns out that the time delay becomes significantly less noticeable when the source of the sound turns with you...

It is easier to locate high pitched sounds if your ears are further from each other. I once lived a place with a shared space with plants and we got a cicada somehow with some plants. It were driving us nuts with it's chirping, but we couldn't locate it until I held a 25 cm cardboard tube to each ear and walked around. My neighbor were laughing so hard, but still was quite impressed when I found the critter :-)

In music production we usually arrange sounds in the stereo field using the pan control - basically altering the balance of the amplitude between the left and right channels. But, just like this video, you can use what's called a Haas Delay instead, which alters the time relationship between left and right instead. The downside is you might run into phase cancellation issues if your stereo mix is ever collapsed into mono, what we call 'mono compatibility'.

This is content. Holy moly. I never knew how badly I wanted to know the things you just told me until you told them to me but I am very glad that you did.

"I don't know if you can tell from the video but Django is actually a GOOD BOY." <3

1:00 Steve experiments science on his better half 2:00 How you detect where a sound is coming from 3:30 Why some sounds are difficult to locate 5:50 How to change the find phone tune for Android (easy) 6:00 How to change for iPhone (you can't) 7:00 How birds make use of this 7:50 Why police sirens are difficult to locate and what can be done about it 9:50 Django is a good boy! Amazing video Steve, as always - and thanks! :)

fun-fact. comment on 8:50 - the exact position can also be located thanks to the structure of our ears, which changes the incoming sound in different ways if it's coming from different directions. If the sound is coming from your right hemisphere, then your left ear will not change the shape of the sound wave, however, the right ear will. And once our brain lined up one signal to the other, it will look at how it was distorted to find out not only the horizontal but also the vertical angle of the incoming sound. Moreover, it does so for multiple sounds coming from different directions, which is absolutely amazing. It really blows my mind how complex is the analysis of the incoming sound, that our brain does non-stop 24/7 like nothing. UPD: dog's can't do this ear-shape-distortion-analysis, which is why they tilt their head every time.

Default tones also just don't work for people that are hard of hearing. My father in law got a new phone - claimed that it was defective because he kept missing calls. Took it back to the store, they said it was fine, etc. Finally, he brought it to me. He is standing across the room, holding the phone, I call his phone, it starts ringing nice and loud, but no reaction at all from him. I take the phone, go in to ring tones and just start making changes while I watch him. After playing a dozen or so with no reaction at all, I play one - he looks up - "You got it to ring?". Set that as his ring tone. Problem solved.

"Make your phone easier to find, with science" ...oh that sounds boring. Oh, it's a Steve Mould video! Clicks

Steve , I’m a huge fan and my son and I are binging on your channel. This is how you mix science with daily problems and that’s when people take more notice. We’ve just hidden each other’s phones and only my phone has the changed tone. Let’s do this. Btw this is helping our lockdown experience. Many thanks Steve.

I'm glad you covered this topic as it confirmed what I suspected to be the case. I always wandered why reversing sirens are now white noise instead of tones with a very narrow frequency band and figured this was probably why. They experimented with having narrow blasts of white noise on ambulances but it just confused people so that idea was abandoned.

excellent video as always Steve. Keep it up!

The problem with this video is the people who need it most can't watch it.

This is how virtual surround sound on games and phones works for headphones! It processes the sounds with Interaural time differences and level delays. HRTF is amazing. Great video!

Love your reaction to the word "iTunes"...lol. I remember one day (long ago) importing a bunch of MP3s into itunes, then later when trying to copy them to another device I found out iTunes converted all the file names to seemingly random long stings of characters, and were no longer playable on other devices. Don't think I've bought an Apple product since.

That bit about the bird calls was super interesting! Always love your stuff! -a 3rd year mechanical engineering student

The ambulances I heard in Paris were much easier to locate by sound than any other I've heard. They use the same siren in Morocco as well. It has two pitches that switch sharply between each other. This gives you both direction due to the inter-aural time difference at the alternation. And it gives you a sense of how fast it is coming or going because it is always the same two pitches so you can sense the Doppler effect. Sirens that smoothly rise and fall in pitch make both speed and location hard to hear.

You could also customize your ears by adding a tube and pointing it around in different places. Instead of the ear-reversing set-up, one with longer tubes that come out at the same place. This set up is also handy for locating the source of noises in particularly noisy, convoluted environments, like the engine compartment of a vehicle.

9:33 That confused look is so funny! It's like he's asking "Steve, what the heck is that?!?"