It’s not that hard to grasp I don’t think. If you understand graphs of soundwaves, 1000119500
Feeling that groove
Submitted 3 days ago by fossilesque@mander.xyz to science_memes@mander.xyz
https://mander.xyz/pictrs/image/3b2eea78-8262-4e29-b785-c6c5577b06e3.jpeg
Comments
Zwiebel@feddit.org 3 days ago
skulblaka@sh.itjust.works 3 days ago
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.
xthexder@l.sw0.com 3 days ago
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.
Natanael@infosec.pub 3 days ago
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
nocturne@slrpnk.net 3 days ago
Cethin@lemmy.zip 3 days ago
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).
captainlezbian@lemmy.world 3 days ago
Bubs@lemmy.zip 3 days ago
This is from a video about headphones. His layman’s explanation at the timestamp is probably the best I’ve heard it told:
prole@lemmy.blahaj.zone 3 days ago
Exactly. It makes sense to me conceptually, but it still blows my mind
unexposedhazard@discuss.tchncs.de 3 days ago
Even simpler to visualize: Its the movement of the membrane of the speaker turned into a physical line.
Eq0@literature.cafe 3 days ago
That explains just a tiny part. There are so many different sounds at the same volume and frequency
gnu@lemmy.zip 3 days ago
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.
qjkxbmwvz@startrek.website 3 days ago
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.
TowardsTheFuture@lemmy.zip 3 days ago
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.
FishFace@piefed.social 3 days ago
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.
Oisteink@lemmy.world 3 days ago
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.
nialv7@lemmy.world 3 days ago
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.
petrol_sniff_king@lemmy.blahaj.zone 3 days ago
He said never. That’s an order.
Psythik@lemmy.world 3 days ago
Simple. Sounds are vibrations. The grooves make the needle vibrate. Those vibrations are amplified.
Rekorse@sh.itjust.works 3 days ago
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?
psycotica0@lemmy.ca 3 days ago
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
olafurp@lemmy.world 3 days ago
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.
SirHery@lemmy.world 3 days ago
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.
Jerkface@lemmy.world 3 days ago
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.
FishFace@piefed.social 3 days ago
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.
ramenshaman@lemmy.world 3 days ago
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. The right channel vibrates diagonally in one direction and the left channel vibrates diagonally in the other direction.
curiousaur@reddthat.com 2 days ago
Fourier transformation.
mika_mika@lemmy.world 2 days ago
It doesn’t do it particularly well and that’s how you know vinyl enthusiasts are smelling their own farts.
realitista@lemmus.org 3 days ago
Yeah it literally just the waveform in physical form. I couldn’t think of a better way to visualize it.
prole@lemmy.blahaj.zone 3 days ago
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.
Blackmist@feddit.uk 3 days ago
Certainly makes a lot more sense than a CD
docoptix@lemmy.world 3 days ago
and CDs are still extremely simple compared to a compression format like MP3
kandoh@reddthat.com 2 days ago
What’s crazy to me is that this technology was used for only a few dozen years before it was replaced and for thousands of years beforehand there was nothing like it
percent@infosec.pub 2 days ago
It’s also interesting that it has made somewhat of a comeback after some newer technologies have faded away
aeternum@lemmy.blahaj.zone 3 days ago
Anything sufficiently advanced is indistinguishable from magic.
I’m convinced this is magic.
RizzRustbolt@lemmy.world 3 days ago
It’s only weird once electrons get involved.
IAmNorRealTakeYourMeds@lemmy.world 3 days ago
things get weirder with your get rid of those electron bois
prole@lemmy.blahaj.zone 3 days ago
I agree, I’m still amazed that this shit works as well as it does.
TankovayaDiviziya@lemmy.world 3 days ago
Add quantum science to the list.
aeternum@lemmy.blahaj.zone 3 days ago
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
Rhaedas@fedia.io 3 days ago
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.
Gullible@sh.itjust.works 3 days ago
Link is borked because of the ! at the beginning. It’s trying to pull a picture that doesn’t exist
mp3@lemmy.ca 3 days ago
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.
freebee@sh.itjust.works 3 days ago
That was very informative, thanks!
Tylerdurdon@lemmy.world 3 days ago
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.
stardom8048@lemmy.world 3 days ago
Interesting, but I think this is largely discredited from the brief research I did?
en.wikipedia.org/wiki/Archaeoacoustics#Discredite…
Cool idea nonetheless.
fistac0rpse@fedia.io 3 days ago
Doesn't really discredit it based on that, but thanks for the article
Valmond@lemmy.world 3 days ago
That’s a lot of screaming!
Actually this is one of the coolest things I have ever seen or heard, thank you!
ramenshaman@lemmy.world 3 days ago
Holy crap that’s wild
realitista@lemmus.org 3 days ago
What the hell are the sounds supposed to be?
FuglyDuck@lemmy.world 3 days ago
Someone playing a recorder or flute like instrument?
Or some one was being tortured.
tamal3@lemmy.world 3 days ago
The description says it’s a violin
Agent641@lemmy.world 3 days ago
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.
Bluewing@lemmy.world 3 days ago
It’s 4:30am and thanks to this thread I’m listening to Dave Brubeck on vinyl…
BoosBeau@lemmy.world 3 days ago
Just count to five and you’ll be alright
Bluewing@lemmy.world 3 days ago
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).
fossilesque@mander.xyz 3 days ago
It’s for science.
JimVanDeventer@lemmy.world 3 days ago
Sound is vibration. A record is a vibration frozen in place.
IAmNorRealTakeYourMeds@lemmy.world 3 days ago
yhea, i can bs, those vynils are usually at room temperature
ChaoticNeutralCzech@feddit.org 3 days ago
Records are very easy to understand. Even without a microscope, you can see periodic patterns on test vinyls with beeps.
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 specifically 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.
Madison420@lemmy.world 3 days ago
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.
ABetterTomorrow@sh.itjust.works 3 days ago
Would love to see that
CookieOfFortune@lemmy.world 3 days ago
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.
SreudianFlip@sh.itjust.works 3 days ago
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.
fubarx@lemmy.world 3 days ago
Agent641@lemmy.world 3 days ago
Calvins’ dads’ explanations were very influential to my shitposting career
Gaja0@lemmy.zip 3 days ago
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.
MonkderVierte@lemmy.zip 3 days ago
Uhm
- ridges cause movement
- mechanic/electric amplification
- movement of membrane in speaker
- membrane moves air = sound
Digit@lemmy.wtf 3 days ago
Some day, I’ll get my (20) albums turned into vinyl.
That day moved a little closer, seeing this.
NaibofTabr@infosec.pub 3 days ago
It’s vibes man.
mvirts@lemmy.world 3 days ago
By choice
Kyle_The_G@lemmy.world 3 days ago
I still don’t get how headphones work and thats always bugged me. how digital files translate into sound and how a little speaker makes that sound.
Hikermick@lemmy.world 3 days ago
What’s that a picture of? Doesn’t like a needle and vinyl to me
Kolanaki@pawb.social 3 days ago
I mean it’s pretty easy if you understand that sound is just a wave of vibration through a medium.
TropicalDingdong@lemmy.world 3 days ago
Beep bop beep boop beep
Valmond@lemmy.world 3 days ago
In Stereo too…
n3m37h@sh.itjust.works 3 days ago
Denjin@feddit.uk 3 days ago
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_Fart_Glitter@lemmy.world 3 days ago
Ah, very similar to the camera (iconograph) filled with fast painting imps.
wiki.lspace.org/Iconograph
Denjin@feddit.uk 3 days ago
That may or may not have been my inspiration
then_three_more@lemmy.world 3 days ago
GNU Sir Terry
Dasus@lemmy.world 1 day ago
A man is not dead while his name is still spoken.
Death can’t have him.
gnuterrypratchett.com
Image
fartographer@lemmy.world 3 days ago
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.
SlurpingPus@lemmy.world 3 days ago
It’s because you played the boring album version, instead of the one and only 1973 live version.
SanctimoniousApe@lemmings.world 3 days ago
I heard their team-building theme song was Madonna’s Into the Groove.
ChicoSuave@lemmy.world 3 days ago
It’s so simple