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Fun fact: nowadays music is still distributed mostly in the 44.1 kHz sample rate, and this odd rate derives from how much it was comfortable to store on a PAL/N
by kozak 3y ago
Fun fact: nowadays music is still distributed mostly in the 44.1 kHz sample rate, and this odd rate derives from how much it was comfortable to store on a PAL/NTSC video tape using devices similar to Technics SV-P100 (when video tapes were the only viable way to store full-quality digital audio). So this number is ultimately derived from line count and frame (field) rate of analog TV standards.
- fathyb 3y agoAlso see the Nyquist frequency: https://en.m.wikipedia.org/wiki/Nyquist_frequency https://en.m.wikipedia.org/wiki/Nyquist_frequency 44.1kHz lets you store all frequencies from 0 to 22.05kHz, which ought to be more than enough for most humans.
- Synaesthesia 3y agoAlmost nobody hears beyond 16kHz, from testing I've done, and I don't think the musical content above that freq is really useful.
- AlecSchueler 3y agoNot listening to much Sachiko M?
- deleted 3y ago[deleted]
- bryanlarsen 3y agoCorrect, but a filter that's flat to 16kHz with an abrupt cut-off above 16kHz would introduce a lot of noise and artifacts, especially with 80's tech. Filters with a gradual roll-off are much smoother, cleaner and cheaper. 44 kHz allows a filter with only 20dB roll off starting at ~16kHz to be used instead. Filters are necessary because if you digitize something at 44kHz, any noise above 22kHz becomes noise at a frequency < 22kHz, aka audible.
- hasmanean 3y agoYeah nobody hears 16khz sine waves. But those high frequencies also make low frequency transients (eg square edges)sharper, and reduce ringing.
- HPsquared 3y agoBut if someone can't hear a high enough sine wave, doesn't that mean the same thing as they can't perceive the sharpness of transients with frequency components above their hearing limit? Surely if you can't hear a frequency when presented as a high-intensity constant sine wave, you're not going to hear it when mixed in with all the other frequencies for a short moment in the form of a step or impulse. Those hairs in the inner ear aren't going to activate, in other words (or their signal won't get through).
- deepburner 3y agoI am not an expert on this but my suspicion is that human ear is not a linear time invariant system and thus it does not make sense to place a hard cutoff at some frequency over which you can not hear. The response might change wrt to the spectral content of the overall sound.
- Washuu 3y agoI can hear 16khz sine waves when played on their own. ¯\_(ツ)_/¯
- jacquesm 3y agoThat's nice, try to conserve it and be careful with your ears. Most adults have already lost enough of their hearing that they can't even hear if an old style CRT based TV is on (which is in the EU 15625 Hz). By the ripe old age of 50 you're lucky to get 10 KHz and when you are at 70 it will be much less than that still. Babies and dogs can hear ridiculously good. The highest note on a piano is still below 5 KHz. Handy resource: https://www.szynalski.com/tone-generator/ https://www.szynalski.com/tone-generator/ Note that higher frequencies are very directional and you may have to move your head around a bit to catch the tone, this works best by finding something you just can't hear and then to move your head around to see if you really can't hear it or if you only can't hear it from that particular direction.
- RajT88 3y agoSeems to be true. When I was younger (in my 20's) I used to be able to hear CRT whines which I guess is in the 15khz range. Less so now, which is too bad. I recall there being specific TV's which I found the whine really soothing while watching stuff. Computer monitors I never heard the whine which is up around 31khz according to some guys on Reddit.
- ummonk 3y agoHave you done any testing with teens or children? I could hear all the way to 23 kHz in my early 20s. Now at 32 I only hear up to 16 kHz (well I can hear a slight tone at 17 kHz but it's very slight).
- mintplant 3y agoThat's not true for me, I can hear higher frequencies just fine. It can cause problems sometimes! Besides the usual annoyances like transformers in old CRTs, there's a video game whose soundtrack has these horrible piercing tones left in, and I've only found a few other people complaining about it online. Most—including the composer, I assume—can't hear them, so are unbothered.
- a_gnostic 3y agoI can hear that. Helps noticing neon lights go bad
- deleted 3y ago[deleted]
- kozak 3y agoSame for 40 kHz or 48 kHz or anything above, but there is (was) a specific reason why 44.1 got chosen.
- FirmwareBurner 3y ago> So this number is ultimately derived from line count and frame (field) rate of analog TV standards. Which itself is derived form the mains frequency of 50 or 60 Hz depending whether you're from the metric or the eagles/freedom land. So the digital sample rate is related to how fast the power pant spins it's generator turbine.
- datpiff 3y ago> So the digital sample rate is related to how fast the power pant spins it's generator turbine. Also based on how incandescent bulbs will appear to visibly flicker at lower frequencies.
- cesarb 3y ago> mains frequency of 50 or 60 Hz depending whether you're from the metric or eagles/freedom land. Sorry for nitpicking, but the huge country I live in uses metric but has 60 Hz for the mains frequency (and our analog TV standard is PAL-M).
- FirmwareBurner 3y agoCanada or Australia?
- foldor 3y agoPAL-M is Brazil as far as I know. Canada is still NTSC.
- rusk 3y agoVery interesting. From Wikipedia: https://en.m.wikipedia.org/wiki/PAL-M https://en.m.wikipedia.org/wiki/PAL-M > [PAL M] is unique among analogue TV systems in that it combines the 525-line 30 frames-per-second System M with the PAL colour encoding system (using very nearly the NTSC colour subcarrier frequency), unlike all other countries which pair PAL with 625-line systems and NTSC with 525-line systems. So presumably PAL M runs at 60 Hz just like NTSC, which again comes back to the domestic AC freq
- 3y ago
- svantana 3y agoIndeed, 44100 may seem like a random-ish number until you look at its prime factors, 44100 = (235*7)^2. In other words, it has a lot of divisors - 81 of them in total, whereas 48000 only has 64.
- flancian 3y agoFor others who were also stumped here for a bit: it seems your text got mangled, likely by triggering markup rules. ITYM 44100 = (2 x 3 x 5 x 7)^2
- tenebrisalietum 3y agoIs it 48000 or 49152? (49152 being 2^15 + 2^14, working well with a lot of binary stuff, but def not divisible by 5 or 10)
- nwallin 3y agoDVD audio frequency is 48,000Hz. When people talk about 48kHz audio they're virtually always talking about 48,000Hz.
- deleted 3y ago[deleted]