6. Beats and Just Noticeable Difference

If you like this Tutorial on Acoustics, please subscribe: / walkthatbass
For more information check out my website: www.thejazzpia...
When you play two notes a wide interval apart on the piano - like a 5th, you hear two distinct pitches. But if you play two notes really close to each other - having a frequency of less than about 30 Hz between them, like a semitone - then we don’t hear two distinct pitches. Instead we hear the a single note at the average frequency, but with a volume which goes up and down over time. This variance in volume is called a ‘beat’ - and creates a ‘wah-wah-wah’ sound. And these beats happen at the difference in frequencies between the notes.

[@yahliamir1]

Finally I understand those weird artifacts that pop up when I use the whammy bar of my guitar on overtones. it was beating all along! great video!

[@evertdude]

i could hear ut from the first change, because i've good speakers hear, you can hear the wavelength, and in the first change you can clearley hear the slow wave lenght and changing more eventually going up more and more

[@ArgoBeats]

This is music for my ears! Thank you! And finally I've understood why lots of violins together sound so velvety while one alone sounds raspy.

[@WalkThatBass]

Exactly right. Glad you liked it.

[@Mmdg634]

All your materials are gold, hopefully future generations can appreciate!

[@ev29xyro]

This is so good! Thanks for the great content

[@snrnsjd]

Excelent video series!

[@wids]

All of youre videos are amazing and informative a f

[@rexchidgey7911]

Such an interesting tutorial. Thank you again WTB...

[@WalkThatBass]

No worries, Rex. Glad you think so.

[@debbypajerowski5690]

amazing! i love your channel!

0:26 I hear some type of up and down in the sound.

[@jyothishkumar3098]

That is the beat frequency

[@dinesha6754]

love your vidoes mate!

[@JohnSmith-iu3jg]

50 : 51 (510/500Hz) is off by 34.283 cents

[@megalo-mangomatuidi3817]

That's how those “Weow” guitars work then, huh?

[@JohnSmith-iu3jg]

The difference between 500Hz and 501Hz is 3.45901 cents #mathematics #logarithmicequations

[@user-ms4jp7ml1y]

Ques: If we hit the note C 220 time per sec (frequency of note A is 220 Hz), will we hear C or A, or both?

[@themelessly]

A, with a lot of unexpected overtones. That's called "sync" in synthesizer. This page will help you. www.keithmcmillen.com/blog/simple-synthesis-part-7-oscillator-sync/

[@user-ix5qy7um6o]

You will hear only C. You can never hear A because it doesn’t exist. You can hear missing fundamental at 50hz when note 1 is 500hz and note 2 is 550hz. You can also hear combination tones but they need loud volumes!

[@ballingchampagne]

how do i generate the sine waves of a sound file that i have and then develop a mathematical function for the sin wave ?

[@clementbenny]

If A 1 = 27.5 hz @ Which Frequency does BPM begin ?

[@bills48321]

Well done. I didn't quite get the second order beat sound at the end. Maybe you could expand this topic in a second video.

[@WalkThatBass]

Hey mate. So a 'first order' beat is when two waves combine in such a way that they cause a variation in amplitude and therefore volume. While a 'second order' beat is when two waves combine in such a way that they cause a variation in wave shape and therefore timbre. So because something is periodically changing in both types, we hear a kind of 'beating' (i.e. some kind of periodic change in sound). But if you listen carefully they sound slightly different. First Order beats create a wah wah wah sound (change in volume). While second order beats don't change in volume but still beat - which is the timbre changing.

[@bills48321]

Thanks!

[@cameronvadnais4388]

I hope you get more views.

[@user-ix5qy7um6o]

You can hear missing fundamental as soon as beat frequency is high enough.

[@priyanujpancake6159]

Isn't JND similar to an LFO in a synthesizer?

[@WalkThatBass]

Similar idea in that LFOs interact with the audible soundwaves and add an effect to the note/sound. I briefly discuss infrasound here: kzbin.info/www/bejne/oqm1d5WQbrGWerM

[@SirWhiteRabbit-gr5so]

I heard beats even at 500-501 hz. example.

[@AlgyCuber]

the 500 hz 501 hz thing, i think it’s called combination tone?

[@jyothishkumar3098]

Beat frequency

[@adamgillespie3393]

my ears nearly fell off on this one

[@TheSentientCloud]

I have a form of perfect pitch where I have extremely good acuity between notes so all those notes sound pitch-wise different lol

[@taran9104]

International Space Station sounds like perfect pitch is a curse, since 99.9% of people don’t have it - and they’re the consumers of your music. I’d be interested to see the positives and negatives of perfect pitch compared, since having perfect pitch doesn’t allow you to manipulate sound in the way most people perceive it

[@minggamratan8921]

I think the amp modulation in synthesis is called Ring Modulation and the pitch modulation as Frequency Modulation...

[@ChalkyWhiteChalkyWhite]

Ring modulation is adding frequencies based on two waves component frequencies. Amp modulation is tremolo or many other forms of modulation.

[@jibbrian417]

Sounds like Deadmau5's Imaginary Friends