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Cake day: July 3rd, 2023

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  • To me it’s much more unclear how sound is first encoded into a digital signal, transmitted as a digital signal through wires and radio waves, and then translated back into sound in a phone. I mean it’s essentially the same physics as the analog electronics, just with a bunch of extra steps added.

    Yeah, this is where sample rate and bit depth come into play. In case you’re curious, digital audio is possible due to the Nyquist-Shannon Sampling Theorem. The TL;DR is that you don’t record a continuous stream of audio data; You just sample the wave at regular intervals by recording the current amplitude. And then you can recreate it on the other end. The theorem states that an analog wave can be perfectly recorded and replicated, as long as you have a sufficiently high sample rate and bit depth. Since human hearing generally tops out at 20kHz, we need to sample the audio signal at least 40k times per second; Most consumer-grade audio equipment uses 44.1 or 48kHz. Phones actually use a much lower sample rate for calls, but more on that later.

    Again, as long as your sample rate is at least 2x the rate of the highest frequency being recorded, you’re able to perfectly recreate the wave. For an example, here’s a gif:

    The image on the left shows the wave being recorded, and the dots are samples. As you add more samples, the reproduced wave gets more accurate. By the time you have 2x the fastest frequency, there is only one possible wave that will fit every sample. Again, human hearing tops out around 20kHz, so we use a sample rate just above 40kHz.

    Phone calls will often put a filter on the high and low ends, and only capture the mid-range. It gives that distinct “this is shitty phone call quality” sound, but means they can use a much lower sample rate; Since they’re lopping off most of the high end with that filter, they may only need a sample rate closer to 15 or 20kHz. Because fewer samples means less data. The intelligibility happens in the mid-range, so that’s what the phone makers (and telecom companies) focus on. This low sample rate is also why hold music sounds so fucking awful. It’s essentially being passed through a “make this sound as shitty as possible while still being intelligible” filter.

    And then bit depth simply determines how detailed each sample is. If you use 8 bits per sample, that gives you 256 potential values per sample. 12 bits gives you 4096. The trade-off is that a higher bit depth means each sample takes exponentially more data; Audiophiles will generally push for higher bit depths, so each sample is more accurate. In contrast, phone calls often use lower bit depths, (again, to save data).

    As for how it actually transmits the data, that’s just 1’s and 0’s. It’s a little more complicated than that, (packets, for example) but in the digital realm, as long as the 1’s and 0’s get to where they need to be, you’re good to go.


  • Ironically, mobile phones being digital makes them easier for many people to understand. The analog circuitry that goes into simply making an analog phone ring is surprisingly complex, let along how they actually function as phones.

    Analog audio is a lot less “computer nerds programming things” and a lot more “scrapped together from some resistors that were ripped out of an old TV. We don’t even know how it turns on, let alone how it functions.” You can literally build a basic microphone with nothing but a balloon stretched across an embroidery hoop, some copper wire, a small magnet, and some glue. It wouldn’t sound good, but it would function as a microphone in some capacity, and at least be able to detect loud noises. And the same goes for a speaker; You could build one out of a red Solo cup, a magnet, some wire, and some glue. It wouldn’t sound good, but you could at least get a basic “sound is being emitted from this” level from it. But if you showed that scrapped-together device to someone, they’d have no idea that it was a phone.




  • Yeah, my “Public Transit” option on google maps is entirely greyed out. This is my daily commute to work:

    It’s always entertaining to see the Europeans go “lol just ditch your car, it has to start somewhere” like it wouldn’t require me to move my entire family across town, (and pay 3x as much rent to live in the city…) Like I don’t even have the option of taking public transit, because there are no connecting lines between my home and my job. Literally none. The nearest bus stop is almost as far away as my job, and it’s in the opposite direction.

    And to be clear, that 2+ hour walk would be on a highway with no sidewalk. I’d be dead on day 1. If I wanted to avoid the highway, the walk would be closer to 4.5 hours; The highway is the only direct path.





  • Mic_Check_One_Two@reddthat.comtomemes@lemmy.worldIt KNOWS
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    5 months ago

    Sure, but this is a little like saying “there is no moral consumption under capitalism, so I choose not to participate in it.” The reality is that the entire society around you is fundamentally built upon something, to the point that only the people who aren’t financially struggling can afford to insulate themselves from it. If someone is financially hurting, telling them “lol just move across town to an apartment that costs 6x as much so you can be near a station and take the train to work” is a fucking deranged suggestion.


  • Typically speaking, you’d want to cut instead of boost. Cutting is easy; You just reduce the volume. Boosting is much more complicated, because you need to “add” signal where none exists. So boosts tend to be noisy and/or outright distorted, while cuts will maintain a clean audio signal.

    Need to boost around 2KHz? Try cutting everything else instead.



  • I’ve used it for basic coding stuff a few times, to great success. Nothing over a few dozen lines, but it’s great when you don’t want to bother looking up the specific functions and syntax for a particular language. For instance, you can have it write basic batch files for you. Then you simply double check it to make sure it’s accurate, (which is much easier than starting from scratch,) and you’re golden.


  • My guess is another CSAM attack. In case you weren’t aware, there are some bad actors who will occasionally use AI to generate CSAM, then post it on any servers they can find using bots to get things to the /All front page.

    And since instances are usually just run by one or two people, response times can be long. Because the instance owner won’t even know anything is wrong until they log on.

    Many instances defaulted to disabling image posts to stop attacks in the short term, so the admins can work on scrubbing the existing posts and banning any users that posted it.


  • I mean, there are sex-averse asexuals. People who are disgusted by the idea of sex. Like it’s just another gross biological function.

    They tend to view the relief from sex the same way using the restroom provides relief. And most people don’t enjoy using the restroom; They just enjoy the relief they feel afterwards.


  • If you’re an artist struggling to get off the ground, one of the best and easiest ways to start making reliable money is to draw smut. If you become known as a smut artist who takes commissions, money comes pouring in left and right.

    And if you’re willing/able to do furry art, your rates just quadrupled, because furries will pay lots of money to get their fursona drawn doing various degen things.




  • Yeah, I used to work a job where I was basically on call for 6 hours at a time, but didn’t need to do much unless something broke. I’d help set things up at the top of the day then tear things down at the end. But in between, I was basically just waiting for things to break. It’s safe to say that I used the fuck out of my gaming laptop and VPN at my desk. Because I obviously didn’t want to try playing games on a company computer.

    I played a lot of single player and idle games at that job, because those are easy to walk away from at a moment’s notice. Just hit pause and you can give your full attention to whatever problem has popped up. Then once it’s resolved, you’re right back where you left off.





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