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> a generation of people is growing who got used to watching digitally compressed audio and video It is unfortunate how today phone calls are often heavily com
by retrac 2y ago
> a generation of people is growing who got used to watching digitally compressed audio and video
It is unfortunate how today phone calls are often heavily compressed. Back in the 80s, 90s, 00s the digital phone network would stream uncompressed PCM audio at 64 kbps and the rest was analog; calls often sounded better back then than they do today. Once we accepted the heavy compression necessary to make early digital mobile phone networks work at 10 kbps or so, we never got the quality back, even though devices have a thousand times more bandwidth available now.
- reginald78 2y agoDon't forget the added latency.
- nyarlathotep_ 2y agoI know effectively nothing about these topics but I recall having that thought the other day. With Apple users FaceTime audio has far higher audio quality than a "typical" phone call Wondering what accounts for the difference. I assumed, if anything, audio compression would be more "aggressive" on web-service based calling than "traditional" calling.
- theandrewbailey 2y agoApple knows which devices Facetime will run on. Traditional calls need to run on old embedded infrastructure that barely has 2 bits to rub together.
- giantrobot 2y agoFaceTime's audio quality is both higher data rate and better audio codecs. FaceTime uses AAC audio and samples at close to the full audible audio band. It also uses a relatively high data rate compared to typical voice calls. LTE and 5G has the option of higher quality voice codecs (EVS) than older cellular networks when using VoLTE or VoNR. They support wider band sampling and higher data rates for better quality audio. Why most voice calls sound bad is inter-carrier compatibility still sucks. Typically calls will downgrade to AMR-WB or AMR-NB (8KHz and 4kHz sampling respectively). FaceTime calls, or any other pure IP voice services, don't need to downgrade codecs to interoperate. They might have to change encoded bitrates based on network conditions but never go with some lowest common denominator codec because another user is on a different network.
- nyarlathotep_ 2y agoAwesome, thanks for this. Where can I learn about these topics?
- bombcar 2y agoA significant percentage of people alive today have never made an analog phone call, or know just how good (and low latency!) it was to literally have two copper wires connecting two phones thousands of miles apart. Direct at the speed of light (almost)!
- KETHERCORTEX 2y agoAs a side effect, they didn't see the trick with dialing a number just by quickly hitting the "receiver rest" lever.
- atmavatar 2y ago...or use a captain crunch whistle to get free long distance calls.
- dboreham 2y agoI'm skeptical there's anyone alive who made an analog phone call over thousands of miles. Local calls yes, but even so I'm pretty old and I never made one because I had no friends on the same CO as my parents' house.
- dsr_ 2y agoHi, I'm alive. East Coast of the US to London, UK, in the early 1980s. Over three thousand miles. Quite expensive. Quality was dreadful.
- kevin_thibedeau 2y agoLong distance between US coasts is thousands of miles.
- shiroiushi 2y agoHis point is that the long-distance connection has been digital for many decades now, even back in the 1980s according to one comment here. He's being hyperbolic of course, since there's people in their 90s and 100s who made phone calls way back when you had to talk to the operator to place a long-distance call. But the general point is valid: how many people here actually remember the days when the connection was all-analog? You would have had to be making LD calls in the 1970s probably.
- snakeyjake 2y agoVoLTE-HD has been a thing for many years and the reason people haven't noticed is that most personal voice calls have transitioned to messaging apps and most of what's left are to or from businesses who have the cheapest VoIP setup they can get away with. Two handsets connected with EVS/VoLTE-HD sound superior to two analog phones on the same circuit, talking to each other. If I call my parents' iPhone using my iPhone the call connects using a high-bitrate EVS codec, crystal clear. I never do that, of course. I FaceTime them.
- kbolino 2y agoDigital phone audio, which was μ-law [1] rather than linear PCM, was not exactly uncompressed. However, the compression involved was very simple, and was designed to offer the 8-bit samples a higher dynamic range than linear PCM would be capable of at the same bitrate (linear PCM would need 14 bits to represent the full dynamic range of 8-bit μ-law). It resulted, by design, in quite clear audio for human voice, as compared to the more aggressive compression used today, but couldn't handle non-voice audio like music as well. [1] μ-law was used in North America and Japan, but a similar encoding called A-law was used elsewhere
- grepfru_it 2y agoThank you for the memory of the horrible horrible sound of someone putting their phone up to a loudspeaker to hear a song.
- garrickvanburen 2y agoI use phone call quality as my prime example of why most people don't actually care about quality.
- supportengineer 2y agoFewer people care about anything any more. We are in a period of decline. Society is collapsing in slow motion, in particular any and all social contracts.
- Brian_K_White 2y agoI don't think this follows, because the function of a telephone call is more utilitarian than anything else. People call for leisure of course, but the phone's part of that leisure activity is still just to convey information not art. The kids all switched completely to txt for the same non-utilitarian conversations once it became available. For all it's low fidelity, it was actually quite high fidelity, in that it was actually very good at conveying all the "voice body language" information besides merely the words. It was just highly optimized for one job and that job was not music.
- mrbigbob 2y agoi dont think its that people dont care about quality but they simply have never experienced a better alternative. an example would be i game on my computer and for years i had a 60Hz monitor and it wasnt til 2020 i upgraded to 144Hz monitor. it is night and day difference in feel that i can never go back to a monitor under 120Hz
- numpad0 2y agoWhy didn't they ever upgrade ISDN to ADSL speeds and beyond, or designed an ISDN-over-PON? Was it cost reasons?
- dsr_ 2y agoOh, they did. It's just that ISDN died in the USA. If someone from Germany can chime in, I believe they had higher-bandwidth ISDN services in the late 1990s onwards.
- bobdvb 2y agoRegular ISDN is 64k and then 128k bonded BRI. You could go to E1/PRI to get 2048kbps for €€€€. In North America ISDN was 56k due to the slower T1 it was sent in and framing.
- sammorrowdrums 2y agoMobile voice call compression sucks so much that about a decade ago, in order to play a live drum audition remotely, I once had to find a space with a landline and printer that would also let me play loudly drums to do it. As a student I had none of those things. In the end I concocted a successful scheme where I would buy a series of phone extension cables, convince my university bar to allow me use their landline for a while, book a drum practice room and wire the cables in a long chain carefully to it, using duct tape to keep the cables safe and above door frames etc. Then I had to join the call, and when it was sight reading time run to the library to print out the sheet music, run back down and play it down the phone. It was intense, but I got the gig and flew off and sailed around the Baltic gigging for a few months in the orchestra/show band which was awesome. I really wish that a mobile phone would have worked, it would have saved me a huge amount of stress.
- red369 2y agoI also miss reliable decent quality phone calls. I sometimes give up on Facetime/Whatsapp/Signal and switch to standard mobile call, or vice-versa, and I can hear that the calls through apps have much richer sound quality, when it's working. The voices are much less tinny, but the delays, echos and periods with just no connection, don't seem much better than standard mobile calls. And the delays and reliability of both is worse than analogue landline calls used to be. I suppose that's to be expected moving to wireless tech, but local analogue landline calls used to be so fast that they had lower latency than a conversation across a room. I know we've gained a lot and I wouldn't trade VOIP for going back to only mobile, or giving up both to going back to landline, but it is a shame quality isn't higher.