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It’s 4:30am and thanks to this thread I’m listening to Dave Brubeck on vinyl…
Just count to five and you’ll be alright
No, it’s better to count 1,2,3,4 - 1,2,3 to keep the beat. (I’ve preformed Take 5 with a Jazz band).
It’s for science.
Well sound is just wiggly air. You put the air wiggle onto the disk so later you can use the disk wiggle to make air wiggle.
He said never. That’s an order.
A cello is just a bit of wood with some stringy Bois, but it sounds like heaven and hell and everything in-between when played right.
Anything sufficiently advanced is indistinguishable from magic.
I’m convinced this is magic.
I agree, I’m still amazed that this shit works as well as it does.
It’s only weird once electrons get involved.
things get weirder when your get rid of those electron bois
Add quantum science to the list.
I’ve watched some yt videos about quantum mechanics. I am FAR too dumb to understand even a few words of what they were talking about lol
Quantum mechanics are the dreams that stuff is made of.
That’s Gold, Jerry!
Tat’s the neat part about it. Scientists dont understand it either.
How computers work is also some form of witchcraft. Even tho I understand the principles behind it, it still is literally magic that we get computers to execute stuff.
Computers are easy, they just do math really really fast. The weird part is how useful math is.
Ah well except it’s really rocks being excited enough to do math.
Nobody understand Quantum mechanics, scientifics only know what it do, but not how.
Sound is vibration. A record is a vibration frozen in place.
yhea, i can bs, those vynils are usually at room temperature
Simple. Sounds are vibrations. The grooves make the needle vibrate. Those vibrations are amplified.
Yeah the basic concept makes sense to me, but I’m still fascinated by the level of detail and instrumentation they can fit into those tiny grooves. It’s not like midi, like a piano roll, it is playing back shit that was recorded. It’s cool af.
Certainly makes a lot more sense than a CD
and CDs are still extremely simple compared to a compression format like MP3
And sound better, too!
How does it seem like multiple sounds come through at the same time though? Say drums and vocals and a guitar, all at once. How does one groove equate to all of that?
Take it back. How does the vibrating air equate to all that? It’s not like there’s a drums bit of air and a vocals bit of air - the vibration is all smushed together. Your brain separates it back out again. That’s why it can take training to separately hear some bits of music, or why you can’t usually pick out individual voices in a choir.
Well if you put multiple waveforms above eachother the form on single waveform.(They all occupie the same space,in this case air, so they can’t be “separate”). This waveform is then recorded and remastered and whatnot. But basically the waves you can see on the vinyl are the “schape” they will have in the air.
Highly basic answer, let’s say the strength of the vocals wave over time is:
5, 4, 3, 2, 3, 4, 5, 4
And drums is:
4, 0, 2, 0, 4, 0, 2, 3
Then you add them together for each time slice and get:
9, 4, 5, 2, 7, 4, 7, 7
And you put that on a record, or out to a speaker, and our ears are able to break that up into the two parts when it hears it. This is the same as when two things are in the room making sound, there may be two sources, but my ear only has one hole, and that hole has one eardrum behind it. The different sounds just add their powers together and hit my ear as one mixed wave.
Alternative answer: magic
Okay, I see this is very simplified, but an instrument consists of more than a strength? Given how many different instruments and voices exist - how many different individual waveforms exist? A flute should have another waveform than a saxophone and my voice is different to that one of your mother.
In theory an infinite amount of different waveforms. But practically speaking, no one would be able to distinguish them by ear, and even oscilloscopes have limited resolution.
Music is super complex and can’t even be described by a single or a few waveforms, unless it’s very simple. Another simplified way to explain all the sounds of music fitting on one “waveform” is to imagine the high frequency stuff happening in between the low frequency stuff. And usually the different instruments and voices don’t happen all at once, they happen slightly one after another, or in sync but intentionally so they affect each other the “right” way. Whatever the “right” way is…
Definitely, but you only ever perceive all that because of the one-dimenaional way your eardrums vibrate, and they vibrate because the air next to them vibrates. If we make the air next to your eardrums vibrate in the same pattern they did when the band were performing, you will hear and perceive the same sound as the band made.
You should be aware that an amplified band is only ever making sound at you through a bunch of speakers whose only function is to vibrate air in a one dimensional pattern.
Separating that all out into different instruments and people and timbres etc is the clever bit, and your brain does that, not the speaker, and you largely learned it as a child.
That’s the neat part, the brain does that using some black magic. You just have to add all the sounds individual waves together and the brain deciphers it.
Yeah, we just have two ear canals. Stereo is basically all your brain will get.
It’s true that the ears receive stereo input, but brain postprocesses it to make surround sound. It uses the time difference from sound hitting your right and left ear to do some black magic and figure out at which angle the sound is coming from.
Another interesting part on this is that the brain is pretty bad at detecting whether a sound is coming from the front or back of the head so it uses visual cues and combines it with the processed sound to make it seem like it’s coming from either the front or the back.
The shape of the ear plays part in the perception of sounds that come directly from front, back, top or bottom.
You can add the waveforms together mathematically. Like if you go into a graphing calculator and plot a sine at 220 hz that’s an A note. Then add two more at 261(ish) and 329, baby you got yourself an A minor cookin’. That’s also what the groove would look like.
264 and 330 (exactly) if you want to justly tune it
That part still kinda mystifies me. I understand that it’s a single waveform and you can just add together all the different waveforms of each instrument but it still blows my mind. Kinda like I sort of understand magnets but it still seems like magic.
With vinyl records it’s pretty cool how it can do right and left channels. For the right channel the needle vibrates diagonally in one direction in the groove and the left channel vibrates diagonally in the other direction.
Yeah it literally just the waveform in physical form. I couldn’t think of a better way to visualize it.
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It’s actually quite straight forward. Inside the record player there’s a small group of highly trained goblins. They watch the needle move side to side and they perfectly recreate the music using their tiny instruments.
Simple.
I got the knockoff version that had an understaffed team of mostly complacent fairies using thrift shop keyboards. I tried playing Hocus Pocus by Focus and they burned down my house and flew off with my neighbor’s cat.
It’s because you played the boring album version, instead of the one and only 1973 live version.
Ah, very similar to the camera (iconograph) filled with fast painting imps.
That may or may not have been my inspiration
GNU Sir Terry
I heard their team-building theme song was Madonna’s Into the Groove.
It’s so simple
How about this one to blow your mind further:
Because of how it was made, they could play back the sounds around the potter who fabricated it.
I thought they had done the same with some Roman parchment, but all I can find are links to stories on that one.
That’s a lot of screaming!
Actually this is one of the coolest things I have ever seen or heard, thank you!
Interesting, but I think this is largely discredited from the brief research I did?
https://en.wikipedia.org/wiki/Archaeoacoustics#Discredited_theories
Cool idea nonetheless.
Doesn’t really discredit it based on that, but thanks for the article
Holy crap that’s wild
What the hell are the sounds supposed to be?
Someone playing a recorder or flute like instrument?
Or some one was being tortured.
The description says it’s a violin
It’s not that hard to grasp I don’t think. If you understand graphs of soundwaves, it’s literally just the wave scratched into the plastic. The movement of the needle dictates the movement of the speaker membrane which results in the same movement in your eardrum. Which is what you percieve as sound.
What I don’t get, personally, is how this one scratched-in groove wave can contain a bassline, a melody and a singing voice and they all can be differentiated coming out of the speaker.
How speakers work in general is just black magic to me, actually.
Exactly. It makes sense to me conceptually, but it still blows my mind
An easier way to understand it, without knowing the math, is to know how it’s made. You play audio into a very similar device and it’s needle scratches the grooves. When you then have a needle pick up the grooves it’s moving the exact same way the needle was forced to move by the original.
It’s similar to how a speaker and a microphone are basically the same device. If you take a speaker and plug it into a microphone input, it still works (though they’re tuned differently so it’s not as good). A microphone has a crystal vibrate, which creates an electric signal. If you play that electric signal into a crystal it vibrates and creates the same sound.
There’s no math or anything being done for this to work. It’s purely mechanical. It’s just a copy of what the needle did when sound was played into it, so another needle running through it recreates the same sound. You can use math to represent it, but none is being done by the device (other than just the laws of physics).
So there’s this thing called a Fourier series…
Basically any wave can be created by adding together individual frequencies, and with some fancy math it’s possible to go the other way with a Fourier transform and get how loud every frequency is (like is displayed in a spectrogram).
I think the real black magic is in how our ears and brains can decode the mess of information coming in and identify meaningful patterns.
A nice related bookmark I have saved. There’s also interactive pert with a slider where you can draw a wave and then add more and more sinusoids to get closer and closer. And of course the square wave, with infinite sinusoids (theoretically).
https://www.jezzamon.com/fourier/This reminds me, Bartosz Ciechanowski has an explainer about the whole sound thing.
That’s because it doesn’t, your brain does
Speakers do the simplest thing possible and literally just vibrate. A recording being played literally just recreates a recorded vibration. It’s a tiny choreography that your ears are incredibly sensitive for.
All the fancy stuff happens in our brains, after our ears has split up the sound around us into different ranges of frequencies (you can think of the hairs in the inner ears as tuning forks). We learn to recognize which frequencies goes together, and then we learn how the frequencies from multiple sources can overlap, and we learn what it all means
The real crazy part is how something as simple as sound can carry so much information and how reliably our brains can tell it all apart and make sense of it
This.
How speakers work in general is just black magic to me, actually.
Well, the big ones anyway. The little ones use crystals.
Nobody knows what magnets are. The best science can tell us is that you shouldn’t drop them into a glass of water.
Why?
The US president told the navy that putting magnets in water could disable them, he also told Fox News twice that no one knows how magentas work.
https://www.snopes.com/fact-check/trump-nobody-knows-what-magnet-is-quote/
I was going to say, “I’m sure technology connections has done a video on this.”
This is from a video about headphones. His layman’s explanation at the timestamp is probably the best I’ve heard it told:
Even simpler to visualize: Its the movement of the membrane of the speaker/microphone turned into a physical line.
That explains just a tiny part. There are so many different sounds at the same volume and frequency
But all sounds are vibration. If you capture the vibration, you capture all of the sound. The “different sounds” are all a single pattern of vibration; it’s the brain and inner ear that decodes the vibration into separate sounds. And hence it can also be difficult to do, depending on what the sounds are.
All the sounds get mixed together as they approach you (as they compress the same air), by the time it gets to your ear it can be represented by one complex wave.
Like when you flatten all the layers in a graphics project.
No, because flattening the layers is a lossy operation but this is reversible.
Hmm good point!
This is a really interesting analogy. I perceive more than I see.
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If you can build up intuition around Fourier decomposition I think it gets much easier to understand.
Multiple things going on at the same frequency are indistinguishable (up to a phase). Lots of stuff going on at different frequency can be separated. Light also has frequency (color) and volume (intensity)—it may be more intuitive to conceptualize in this way.
Ironically, I work a lot with Fourier Transform. Still feels like magic. I even taught it! I’m trying to develop more intuition about it (vs hard knowledge)
I forget most of them, but I remember there being several concepts in calculus that straight up felt like magic once I finally understood them.
Yeah, waves add. Which, well they add from the center which looks weird and bumpy. What’s more amazing is how good our ears are at picking out differences (it’s like 100x more sensitive to differences than other senses) so it can tell what all those individual waves would be so we can still hear the guitar vs drums vs bass vs vocals when it’s all one wave combined.
Magic!
It’s not that hard to grasp if you read up a bit. You are probably born early 1900’s and have never heard of stereophonic recordings. But fear not!! What you are seeing is left + right channel (mono). The left - right channel is encoded vertically. So your left channel is mono + vertical divided by 2, and the right is (mono - vertical) divided by 2.
Consider this: every record I play has a faint recording of the room, every time it has been played, since no turntable or cartridge is perfectly isolated, and, being diamond rubbing against vinyl, will leave some trace of the room sound behind.
It’s really simple.
Sound is air vibrations at different strengths (volume) and frequencies (pitch). Taller waves are loud. Thinner waves are higher pitched. The math looks like this:
Volume * sin( Pitch * time)
Generally, low pitch sounds are louder and easier to see in a sound wave. A kick is really easy to spot. The rest of the weird janky movement of the sound wave is like a bunch of these equations added up to create the sound… generally.
The trick to understanding sound is that it’s a difference over time. The change in pressure is registered by your brain. A record player is literally just the physical transcription of this math and the speaker is just oscillating back and forth to reproduce the sound.
Okay maybe it’s not super simple, but I hope this helps.
tl;dr: magic
What’s that a picture of? Doesn’t like a needle and vinyl to me
It looks like an electron microscope image, hence it being black and white and so close up
If I’m not mistaken it’s from a shot by the YouTube channel Applied Science. Ben is an absolute genius
A microscope? That must be a tiny record player. The needle arm looks like it’s made of clay
I’m a microbiologist. That’s pretty normal. Things that look smooth and even when viewed normally frequently look different when significantly magnified. Your eyes can’t resolve the fine details so your brain fills in the gaps.
](https://www.youtube.com/watch?v=3DdUvoc7tJ4)The video explains how a single needle can play stereo sound, but in doing so explains how the basic idea works before going into the incredible design to do two channels.
That was very informative, thanks!
Link is borked because of the ! at the beginning. It’s trying to pull a picture that doesn’t exist
As a general FYI, you can make a clickable YouTube thumbail like this
[](https://www.youtube.com/watch?v=3DdUvoc7tJ4)Just replace the videoID in the thumbnail and URL.
I tried to duplicate what you have (which works in your example) but it broke it badly, so I left it. One day all the Fediverse will be universal in how it works.
Records are very easy to understand. Even without a microscope, you can see periodic patterns on test vinyls with beeps. And sound being periodic motion is also obvious from string and percussive instruments.
You can even see tracks starting and ending on pressed CDs under the right lighting with your own eyes. I wonder, is the encoding of silence (approx. 2 seconds) really that different or does the density of grooves or pit/land pattern intentionally differ to help the player seek there faster? I know that uncompressed audio naturally results in a repeated pattern when silence is encoded but given the 8-to-14 modulation and other error correctiion techniques, I find it hard to believe it would result in significantly different density unless they specifically added a special mode just for encoding silence that makes the track brighter-colored for easier coarse seeking.
Theres a graphic somewhere I’ll try to find that shows a bird call as a sound wave then a picture of record topography of the same call that makes it fairly obvious.
Gramophones are also fairly illustrative given that the needle directly acts on a diaphragm that is directly connected to a bell shaped horn.
Would love to see that
Long runs of no changes is generally undesirable because it makes it harder to know where the reader is. So you’d want some type of coding to make sure you see changes occasionally regardless of where you are. For CDs, it seems like each byte is converted into 14 bits, where the longest run of zeroes is 10.
I know, among other things there is a time code inserted very frequently between audio data, without which seeking would not be possible at all. However, the audio uses over 90 % of the data so it’s largely responsible for the overall appearance of the track.
It doesn’t seem like there’s a pseudorandom coding applied, so repeated patterns should show up visibly. I’ve never really examined it myself though.
Welp, I remembered this post and it’s most likely valid CD-audio, just with awful noise.
Cool! Good to know this software is out there.
Calvins’ dads’ explanations were very influential to my shitposting career
