The “432 Hz vs. 440 Hz” conspiracy theory | Hacker News
The “432 Hz vs. 440 Hz” conspiracy theory | Hacker News Hacker News new | past | comments | ask | show | jobs | submit login The “432 Hz vs. 440 Hz” conspiracy theory (jakubmarian.com) 447 points by mweibel on Oct 24, 2016 | hide | past | favorite | 315 comments anigbrowl on Oct 24, 2016 | next [–] I have been following this for years, being both a sound engineer and a bit of a hippie who knows a lot of other hippies. The basic issue is that 432 is a numerologically interesting number compared to 440. So if it's more interesting it should be better for artistic purposes, goes the argument. However this falls flat as soon as you consider that the 432 is only interesting relative to the completely arbirtrary duration of a second. There is nothing special about the second from a human psychoacoustic point of view. We could have standardized on a longer or shorter time interval, but since we'd been using the Babylonian-originated divisions for centuries in the west the second is what we ended up with.But unless the music also contains some 1Hz modulation (or a power-of-two multiple thereof) then the 432 base frequency isn't related to anything fundamental in musical terms. Speaking as a DJ, if you take a track and play it a little bit faster or slower it still sounds great or awful as at the default speed in most cases. 432Hz vs 440Hz is a ~2% difference, while DJ equipment commonly allows for +/-10% pitch variation so you can match the pace of different tracks smoothly while people are dancing. Only the very tiny number of people with perfect pitch find this disorienting to listen to. If there were really something special about the duration of the second and the base pitch relative to that, you'd have expected it to emerge from dancefloors years ago. In reality 432Hz is basically cargo cult numerology, something fun to think about when you are not having any success coming up with a kickass tune. And kickass tunes derive their quality from the relative rations of the note pitches, not from some absolute Magic Frequency.Trust me on this. I really love numerology, sacred geometry and so on, and I try to integrate this into my artistic work regardless of medium. I would love for there to be some special key that would unlock the gate to cosmic/ biological/ quantum harmony and allow my artistic work to automatically echo the heartbeat of the universe. I'm a mystic by temperament and have been looking for such things my whole life. I would go so far as to say I have some religious faith in the significance of such things. But this ain't it. mrb on Oct 24, 2016 | parent | next [–] "if you take a track and play it a little bit faster or slower it still sounds great or awful as at the default speed in most cases."Yup. Another example: in most of the world (where the television system is PAL or SECAM) movies are played on TV or released on DVD at 25 frame per second. But to achieve this frame rate, they take the theatrical film release at 24 fps and speed the video and audio up by 25/24th (4.17%). Of course almost nobody knows this because nobody notices it. https://en.wikipedia.org/wiki/576i#PAL_speed-upFor NTSC, the film release is sped down by a much smaller amount (0.1%) during the 3:2 pulldown to adjust from 30 to the exact 29.97 fps that NTSC needs. criley2 on Oct 24, 2016 | root | parent | next [–] Another example is the kind of dastardly television trick of increasing the speed of a television program to shorten it and thus increase the amount of advertising space that can be run alongside the program.https://www.youtube.com/watch?v=z6i1VVikRu0This video claims that TBS is currently increasing the speed of Seinfeld episodes a whopping 9%, reducing a 25 minute episode to some 22.5 minutes. nullc on Oct 25, 2016 | root | parent | next [–] "mpv -speed 1.1 file.webm" ... get 10% of your watching things time back, it does pitch correction, often its unnoticeable.Technology can work in your favor too! jmiserez on Oct 25, 2016 | root | parent | next [–] VLC can do this too:Speed up: ] key Speed down: [ key Normal speed: = key 50CNT on Oct 25, 2016 | root | parent | next [–] I use that to watch slow lectures at anywhere to 1.8x to 2.3x the speed. Turns a 40 minute lecture into a 20 minute lecture. geon on Oct 25, 2016 | root | parent | next [–] Some people one youtube speak really slowly, or are unprepared. The 1.25x speed button is great for that.Also, some youtubers speak way too fast. Slowing them down helps comprehension a lot, I find. harperlee on Oct 25, 2016 | root | parent | prev | next [–] I am used to speed up things, but last weekend I suddenly realised I can also slow down engrenages (a French show recommended in another HN thread, by the way) and suddenly I can understand so. much. French. It's like magic! tripzilch on Oct 27, 2016 | root | parent | next [–] Not many people are aware that this is in fact the natural way spoken French sounds like in France, because of a difference in air composition and thus the speed of sound. jmiserez on Oct 27, 2016 | root | parent | next [–] Uhm, no that's definitely not true. fn1 on Oct 25, 2016 | root | parent | prev | next [–] Stanley Kubrick would have hated this. ;)http://www.cinemablend.com/new/Message-From-Stanley-Kubrick-... dclowd9901 on Oct 25, 2016 | root | parent | prev | next [–] You absolutely see it in TBS broadcasts of Family Guy, where they can get away with speeding up the show without impacting its look and feel tremendously. kikimaru on Oct 26, 2016 | root | parent | next [–] Can't skip frames when there are none. Torgo on Oct 24, 2016 | root | parent | prev | next [–] USA network used to do this. phire on Oct 24, 2016 | root | parent | prev | next [–] Of course almost nobody knows this because nobody notices it.Though, I can now instantly tell if I'm watching a PAL or NTSC version of Star Trek TNG based on the the first few bars of the opening song.Which is weird, because I don't even have pitch perfect hearing and I'm not even that musically inclined. tikhonj on Oct 24, 2016 | root | parent | next [–] I'm guessing you've watched a lot of Star Trek? I figure this is just the human mind's wonderful proclivity towards learning patterns.I was actually thinking about a similar but less subtle example: I use a transit system that involves tagging on and off with an RFID card (Clipper on Caltrain). When you tag your card, it makes one of three different noises depending on what happen—and I couldn't possibly tell you which one corresponds to what. But if I'm actually using it and I make a mistake, I notice immediately because I'm so acclimated to the pattern it normally makes!If I hadn't realized this, the UI for the system would have looked absolutely terrible. The different beeps are the auditory equivalent of "mystery meat navigation" but even worse because they don't carry any semantic meaning at all. But because I always use the system in the same way and the noises were consistent, it actually works really well even if I never consciously learned what noise corresponds to what.(The fact that there are wrong ways to use the system is bad design, but it's a function of how the whole train system is set up, not the fault of Clipper's designers.) ytpete on Oct 25, 2016 | root | parent | next [–] I wouldn't be surprised if there was some psychology behind the choice of sounds when you tag the transit card. Just like visual "affordances" in UI design, there may be certain audio characteristics that people will associate with "good" vs. "error," for example. I recall one study showing that people almost universally feel certain shapes and word sounds are "friendlier" than others (albeit by very subtle margins). And I believe in many languages people interpret pitch inflections to tell when a sentence is continuing vs. finished - think about reading someone a serial number out loud, and how if you were to pronounce the last number the same as all the others it will sound like you left the sentence dangling, with more digits still to come.I'd be really interested to read anything more concrete about audio affordances though, if anyone knows of links to further research, etc! harperlee on Oct 25, 2016 | root | parent | next [–] I can list at least three linked ones: with two beeps, if the second's pitch is higher, means "on" or "ok" or "up", whereas if the second's pitch is lower, the other way around.A fantastic book on how these are all related is "metaphors we live by". I'd expand on this but I'm typing on mobile and on a hurry. But seriously: read the book. It takes a long afternoon. It's great, short, illuminating, and not excessively dense or padded. anigbrowl on Oct 27, 2016 | root | parent | prev | next [–] Yeah, there's quite a lot of this but I can't think of any good references offhand. When doing audio logos I've always looked to catchphrases and famous movie quotes and tried to emulate the underlying intonation/cadences. I'm not aware of this knowledge being systematized anywhere though. ytpete on Nov 2, 2016 | root | parent | next [–] "Audio logos" - that's a fascinating concept I've never really thought about. Any recommended reading about that field? schoen on Oct 25, 2016 | root | parent | prev | next [–] There are several different Clipper beeps:* One beep - successfully paid fare* Two beeps (different) - successfully paid fare, and you're about to run out of money on your card* Two beeps (equal) - tagged off (e.g. on Caltrain or San Francisco Bay Ferry)* Three beeps - read error or insufficient valueThere might be others. Indeed, they've introduced a quieter "here is a Clipper reader" beep to help visually impaired people locate them: https://vimeo.com/183916243 hammock on Oct 24, 2016 | root | parent | prev | next [–] You can train your brain to remember pitches. Try humming your favorite song, then play it and see if you picked the right key. I did this as a game with a friend one afternoon with maybe 80% success rate across 50 songs. droidist2 on Oct 25, 2016 | root | parent | next [–] Does that mean you can train yourself to have perfect pitch? BenElgar on Oct 25, 2016 | root | parent | next [–] As I understand, no. There's some suggestion that small children, usually under the age of 10, can acquire perfect pitch, but no adult has ever been documented acquiring it.Source: http://www.zainea.com/absolpitch.pdf stupidcar on Oct 25, 2016 | root | parent | next [–] There seems to be some controversy about this though. I've seen other papers[1] claiming that adults can acquire it, albeit only to a limited extent.[1] e.g. http://www.sciencedirect.com/science/article/pii/S0010027715... hammock on Oct 25, 2016 | root | parent | prev | next [–] That seems like a logical conclusion pimlottc on Oct 25, 2016 | root | parent | prev | next [–] I know what you mean, when I was living in Australia I could swear the voices sounded off on The Simpsons. pge on Oct 25, 2016 | root | parent | prev | next [–] Might not be the change in pitch you are noticing but the speed of the music triplesec on Oct 25, 2016 | root | parent | prev | next [–] This explains the years of confusion I've suffered noticing sharp pianos in films. I could never work out what was wrong with American film pianos! Thank you, seriously. Buge on Oct 25, 2016 | root | parent | next [–] The European (PAL) ones are sharp. The American (NTSC) ones are accurate (or very very slightly flat). triplesec on Oct 25, 2016 | root | parent | next [–] Late night error, thank you for pointing that out. European etc PAL formats go sharp when transcribed to. So American and all films transcribed into PAL go sharp, which happens a lot. So it's not the origin of the film, but the (usually) PAL format I historically watched them in that caused this.And in cinema they were better (I seem to remember Geoffrey Rush 'playing' Rachmaninov 3rd Piano Concerto in that film, at excellent pitch in the cinema), so I knew they were sometimes right. But i think the tape, TV and DVD formats I'll have rewound most often in perplexity.Another confounding: living in California a lot and not having incorrect pitch on local copies. And nowadays, when sources are digital, bit may have originated from analogue recordings, it's now very unclear what to expect. qilo on Oct 25, 2016 | root | parent | prev | next [–] > For NTSC, the film release is sped down by a much smaller amount (0.1%) during the 3:2 pulldown to adjust from 30 to the exact 29.97 fps that NTSC needs.No. For NTSC they just drop (throw away) 1 frame from every 1000 frames, so there's no speed-up or speed-down in audio track. anigbrowl on Oct 27, 2016 | root | parent | next [–] This is incorrect. I worked for a decade as a film sound engineer. If you don't implement the 0.1% pull-up/pull-down, then sync will begin to drift noticeably.https://www.lynda.com/Pro-Tools-tutorials/Understanding-vide... Firadeoclus on Oct 25, 2016 | root | parent | prev | next [–] There must be a speed-up since the audio track is not divided into frames. Dropping a 33ms chunk of audio would be very noticeable. qilo on Oct 26, 2016 | root | parent | next [–] No, you don't have to alter audio in any way, you just leave it untouched.Let's say you have 100 seconds of film material with corresponding audio duration. That would be exactly 2400 frames, because film is 24 fps. When you do 2:3 pulldown (that's one of the methods used to do telecine, i.e. film conversion to television format) you'll get back exactly 3000 video frames. But in NTSC format, (if you'll leave audio untouched, i.e. it's duration didn't change, it's still is 100 seconds) for 100 seconds of video duration you must display 2997 video frames, not 3000. So you just throw away 1 frame from every 1000 frames to get the exact 29.97 fps.Doing this, at worst case you'll get audio/video desynchronization of 33 ms, which I don't think is noticeable (I tend to visually notice desynchronization when it's at about 100 ms or more). But if you'll drop that 1 excessive frame in the middle (not at the end) of the sequence of 1000 frames, you'll get audio/video desynchronization which only varies from -16 ms to +16 ms. Which is not worth the trouble of fixing this by going the other way around it: leaving video untouched and slowing down the audio by 0.1%. caf on Oct 24, 2016 | root | parent | prev | next [–] The first time I remember hearing about this was in regard to the semi-famous "Wizard Of Oz / Dark Side Of The Moon" combination, which supposedly only works at the theatrical frame rate. mxfh on Oct 25, 2016 | root | parent | prev | next [–] If anyone wonders where the odd NTSC frame-rate ratio originated from, Matt Parker (standupmaths) did a comprehensive video, with some original write-up on this recently: https://www.youtube.com/watch?v=3GJUM6pCpew NickNameNick on Oct 24, 2016 | root | parent | prev | next [–] Whilst conversions that speed up video do happen, It's not really intentional or desirable.A friend of mine bought the DVD of 'Rent' when it first came out in our region. A month or two after it came out, the DVD got re-issued because it's a musical, and people had been complaining that the conversion had been messed up. I think she got the re-release for free. duskwuff on Oct 24, 2016 | root | parent | next [–] Rate changes are a bigger issue for musical features like Rent, as it makes them difficult to play along with. For a more typical dramatic feature, it's less noticeable. cyphar on Oct 26, 2016 | root | parent | prev | next [–] There's a really interesting video by Matt Parker about why 29.97 is the magic number.[1][1]: https://youtu.be/3GJUM6pCpew dhimes on Oct 24, 2016 | parent | prev | next [–] The second is defined as the time it takes for two hyperfine levels of the ground state of the 133 Ce atom to make 9,192,631,770 transitions. How is that not special? johncolanduoni on Oct 24, 2016 | root | parent | next [–] Because that definition was grandfathered in such that it matched the previous definition of a second up to the previously specified precision. You've just moved the arbitrary part to the number 9,192,631,770. The same thing was done for the meter (defined such that the speed of light is precisely 299,792,458 m/s), ampere (current which produces 2 × 10−7 N/m of force between two parallel conductors). There's plans to do the same thing for the kilogram using Plank's constant, but for now we're stuck with the prototype kilogram whose mass unfortunately changes more than we'd like.I could see making a case that Planck time is special enough for 440 vs 432 to matter, but it is so far off the scale of human hearing that its even integer points would form an effectively continuous scale when it comes to audio. Angostura on Oct 24, 2016 | root | parent | next [–] I suspect the poster's tongue was firmly in his or her cheek. dhimes on Oct 24, 2016 | root | parent | next [–] Indeed. But damn, this is a tough crowd :) anigbrowl on Oct 27, 2016 | root | parent | next [–] I LOLed akira2501 on Oct 24, 2016 | root | parent | prev | next [–] > current which produces 2 × 10−7 N/m of force between two parallel conductorsHate to be a stickler, but: "...conductors of negligible cross-section and of infinite length." It's still one of my least favorite SI definitions. MereInterest on Oct 24, 2016 | root | parent | next [–] If anybody wants to read lots of commentary on units and their definitions, take a look at the data sheets for the Frink language. The ampere and the candela are two of the more irksome ones, as described by the author.https://frinklang.org/frinkdata/units.txt ghaff on Oct 25, 2016 | root | parent | next [–] Fascinating. Thanks! At one point I wrote a unit conversion program before such things were ubiquitous and I included a field that had information about the units involved. In service of this, I copied a number of older books on measurement units though I never got around to folding most of this into my program. largote on Oct 24, 2016 | root | parent | prev | next [–] Couldn't the Kilogram be derived from the Liter, which in turn can be derived from the Meter? From what I recall:- 1 Liter of pure water at 4 Celsius is 1 Kg.- 1 Liter is a cube with 10 cm on each side. cc439 on Oct 24, 2016 | root | parent | next [–] Generating a perfectly homogenous 4C over an environment large enough to contain a kilogram of any useful substance is going to be incredibly difficult and mearusing it even moreso. There's a reason every unit of measurement aside from mass is derived from an electrical property; we can measure electrical properties down to ridiculous precision, measurements small enough that all measurement uncertainty is removed. geon on Oct 25, 2016 | root | parent | next [–] Werent they trying to count the atoms in a perfect sphere of silicon? largote on Oct 25, 2016 | root | parent | prev | next [–] That is good to know. Retra on Oct 24, 2016 | root | parent | prev | next [–] You could do that, but if you're trying to set standards, you have to take into account your ability to measure these things reliably and accurately. (It doesn't do any good to set standards that nobody can conform to because their equipment is never sensitive enough to use them.) Can you measure a liter more accurately than you can measure a kilogram of some reference material? vacri on Oct 24, 2016 | root | parent | prev | next [–] I always thought it was amusing that the basic definition of the liter was taken at 4C, but that lab equipment was calibrated at 20C... largote on Oct 25, 2016 | root | parent | next [–] I think that's because 4C is the point where water is the densest, whereas 20C is a comfortable room temperature. detaro on Oct 25, 2016 | root | parent | prev | next [–] Interestingly enough it started out as being defined as 1 dm³ in the 18th century, then in the early 20th century was defined through water at highest density, then in the 60s back to 1 dm³. timv on Oct 25, 2016 | root | parent | prev | nex… truncated (79,793 more characters in archive)