Why do beats sound pleasing to the ears?

  • #1
iVenky
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What's the reason why beats sound pleasing to ears? It looks like the tones that beat with each other a lot more in general sound pleasing.
 

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  • #2
berkeman
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What's the reason why beats sound pleasing to ears? It looks like the tones that beat with each other a lot more in general sound pleasing.
Are you sure you aren't thinking about "vibrato" instead of beats? Beats would generally refer to a longer-term spatial interference, versus the shorter-term musical vibrato emphasis...

https://en.wikipedia.org/wiki/Vibrato

Beats are annoying to me (depending on the situation). Vibrato is a normal part of music and singing...
 
  • #3
Orthoceras
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I would agree that beats are often pleasing. Good examples are wine glasses, and bells, such as the Big Ben.
 
  • #4
jack action
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Because we like patterns. The main reason for our survival is that we can identify patterns. When there is a pattern, we know what will come up next, thus they help us predicting the future. So we developed a "taste" for it. And just like food or sex, they make us feel good such that we want to look for them, anywhere they are.
 
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  • #5
OCR
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Beats are annoying to me (depending on the situation).


Lol. . . I'll make a wild guess about the "depending on the situation" qualification, and

assume it's called a heartbeat. . . . :wink:

.
 
  • #6
tech99
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What's the reason why beats sound pleasing to ears? It looks like the tones that beat with each other a lot more in general sound pleasing.
I suspect that a single pure tone is tiresome for the brain; if we have near-harmonics, which create slow beats, it gives the brain something to do sorting it out.
 
  • #7
sophiecentaur
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What's the reason why beats sound pleasing to ears? It looks like the tones that beat with each other a lot more in general sound pleasing.
IS this a question about harmony and dissonance and how we started having subjective likes and dislikes of musical chords - or at the 'beats' you refer to associated with low frequency 'modulation' of a sound. I suspect it's the musical option?
 
  • #8
A.T.
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Lol. . . I'll make a wild guess about the "depending on the situation" qualification, and

assume it's called a heartbeat. . .
Which might be a reason why we like beats, since we hear the mother's heartbeat even before birth.

I also think this thread should be moved to the biology sub forum.
 
  • #9
sophiecentaur
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I also think this thread should be moved to the biology sub forum.
Maybe but if the structure of our hearing system comes into the thread then the Physics of the process is highly relevant. (I have never read a suggestion that Colour discussions should go to the Biology sub forum and we get those on a regular basis.)

Maybe we should wait for some reaction from the OP before we charge off (in PF fashion) in a direction that could bore, confuse or frighten the OP and we may never get a reply.
 
  • #10
A.T.
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I have never read a suggestion that Colour discussions should go to the Biology sub forum ...
The question is about finding beats pleasing, not about the physics of the ear. It's somewhere between biology and psychology.
 
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  • #11
sophiecentaur
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not about the physics of the ear
Do you know that? In an organ as clever as the Ear, I'd be very surprised if there wasn't quite a lot of filter theory and signal processing involved (temporal and frequency domain filtering). A brief look at Wiki on Hearing has plenty of serious Engineering and Physics mentioned. We have matching networks, resonant frequency sensors and a common mode rejection mechanism. I'd bet your average Biologist would struggle with that unless they had already done the hearing bit in detail.
If all that mechanistic stuff has no effect on what we consciously hear and appreciate then I'd be very surprised - even if it's only to involve non linearities and intermodulation.

See what the mods all think.
 
  • #12
A.T.
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A brief look at Wiki on Hearing has plenty of serious Engineering and Physics mentioned.
Everything in natural sciences is related to physics. But a question about why humans like something will likely get better answers in a biology / psychology forum, then here.
 
  • #13
What's the reason why beats sound pleasing to ears? It looks like the tones that beat with each other a lot more in general sound pleasing.

I barely know anything about this, but I think there is maybe some interesting Physics here. Helmholtz did some work on consonant/dissonant beat frequencies (I found this) but it isn't a perfect theory.

On beating... there are several ways to tune a piano, and one of the older methods is the so-called "Pythagorean temperament" which is loosely based around tuning a series of notes separated by perfect fifths (frequency ratio 3:2) and filling in the remaining notes up and down the various octaves. A problem with this is that the circle of fifths doesn't quite close (see the Pythagorean comma) and you also get an awful sounding diminished sixth due to a beating effect that makes it sound a little bit like a wolf howling (dissonant "wolf interval"). That's one reason that even-temperament is more common today.
 
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  • #14
sophiecentaur
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Everything in natural sciences is related to physics. But a question about why humans like something will likely get better answers in a biology / psychology forum, then here.
Let's see how it runs first. If you can't see the scope for a Physics based discussion about the psychology of hearing then you are not forced to contribute. If the OP wanted straight biology and psychology then why post on PF in the first place? Think outside the box.
 
  • #15
sophiecentaur
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A problem with this is that the circle of fifths doesn't quite close
It's amazing that we actually enjoy music at all when it all seems to be built upon inconsistencies. I imagine that any early work would have been wavelength / string / pipe based and pretty crude. Problem would have been that the early 'Scientists' were all looking for common patterns and would fit the evidence to the theory (Music of the Spheres for instance) because they were all assuming some divine influence.

These days instrumentalists have to fight their instruments to pull the notes to an even tempered scale and 'key colour' is probably not so obvious as when brass instruments were just one length. Yamaha changed all that - or perhaps Irving Berlin got there first with his Transposing Piano.

There is more to 'beating' than just getting a pleasing chord sound. A good solo singer or player will play a fraction higher than the accompaniment in order to stand out and impress. I think there's a similar trick with the dominant chick in a nest so that the parent will feed them more than the other chicks. Babies know (learn) what notes to sing / shout in order to get your attention - that sound is definitely not 'sweet' and must have a well designed spectrum.
 
  • #16
hutchphd
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There is more to 'beating' than just getting a pleasing chord sound. A good solo singer or player will play a fraction higher than the accompaniment in order to stand out and impress. I think there's a similar trick with the dominant chick in a nest so that the parent will feed them more than the other chicks. Babies know (learn) what notes to sing / shout in order to get your attention - that sound is definitely not 'sweet' and must have a well designed spectrum.
The most telling indicator I know is that the depth of tone in a pianoforte (to be formal) is greatly dependent upon the skill of the tuning person. Most of the strings are doubled and tripled and detuned ever so slightly when the piano is "in tune". Of course even-tempering is probably one reason for this process and the multiple string design
 
  • #17
sophiecentaur
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The most telling indicator I know is that the depth of tone in a pianoforte
I had an old piano which wouldn't hold the proper tension so it was tuned low. Nothing to lose, I tried tuning it. Total nightmare! That was despite reading what to do on the internet whilst I was doing it. Can you believe that?
The sound did vary noticeably as I stagger-tuned the string sets. Interesting.

The only good news about that piano was that Brighton (UK) council removed it for me at a very reduced rate because I was a senior citizen. They did manage to crack a floor tile on the front path but it was an honourable scar.
 
  • #18
hutchphd
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Yeah I had a similar experience although I could see that it would be very satisfying to do well. New respect for the piano tuner (probably not a booming profession over the past half century).
 
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  • #19
sophiecentaur
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"Hey, you with the broken nose - play the piano."
"I don't have a broken nose."
Thwack!
plink plonk plink plonk!
 
  • #20
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the evolutionary arguments above are just personal speculation, no real way to prove that a widespread preference for certain types of sounds over others has anything to do with survival on the primordial savannah. Not really sure if the premise is a universal preference. Harmony is exceedingly rare outside of European Music and instrumental preferences run the gamut from the pure sine-wave like beat-less tone of flutes to the complex non-harmonic partials of gongs or bells.
 
  • #21
sophiecentaur
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the evolutionary arguments above are just personal speculation,
Yes. You are right but evolution can very often account for our characteristics. The identifiable structures in the ear are very much Engineering - based and that is surely a result of evolution. Sound as an intra species, social communication is as likely to have been a strong evolutionary influence so the word 'survival' has more to it than the ability to dodge the (anachronisitic) sabre tooth tiger.
Harmony is exceedingly rare outside of European Music
It's true that we tend to hear only small ensembles playing anything but European music and it's in ensembles that formal harmony is easiest to spot. Multi note instruments require high technology, for consistency. Western culture has been very strong and used technology to get to the modern set of instruments that are used. Even our classical and baroque favourites were not composed for modern orchestral instruments and modern harmonies have 'advanced' to make use of modern instruments. All this goes out the window, of course with the introduction of the fuzz box etc.. and harmony, as such, is taking more of a back seat in the new musical developments.

'Other' music has probably only survived as well as it has by sticking to its 'traditional based' with traditional instruments, as defence against the all pervading western culture. Non- western music has perhaps has more in common with the sounds of 'early' western folk music.

You seem to be making the (very reasonable) suggestion that harmony is a learned fashion in some cultures. I agree but that is also a matter of previous evolution and the software we use evolves is always based on the available and convenient hardware.
 
  • #22
sandy stone
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Regarding the OP, it is not a given that beats are pleasing to the ear. Quite a few twin-engine motor boats have fairly elaborate equipment to synchronize the engine speeds, just to eliminate the beat of slightly out-of-sync engines. I, and apparently many others, find it annoying.
 
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  • #23
sophiecentaur
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it is not a given that beats are pleasing to the ear
LF beats can be very upsetting or at least very noticeable (piano strings etc). Sub sonic beats can be used as a military weapon (but the guy with the sound equipment needs protection too.)

What you say about boats would also apply to prop aircraft. Iirc, the de Havilland Biplane I flew in once didn't have it. It was like having two London buses ticking over, neither side of me. A very nostalgic sound.
That diagnostic sound of a Chinook helicopter could be due to the paired rotors. I guess it could count as a beat (?).
 
  • #25
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This thing was a bit on the nasty side, too. . .

Republic XF-84H Thunderscreech

Scroll down to. . . Noise.


There used to be a "sound clip" in the article, but it seems to have been edited out ?

Of course, there is one on . . . YouTube. . 🎧

.
 

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