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Voice quality has never been good on cellphones, it's actually far below even so called FM-quality, which is far below CD-quality. The microphones are capable o

Voice quality has never been good on cellphones, it's actually far below even so called FM-quality, which is far below CD-quality. The microphones are capable of recording voice in a much better voice quality than what is currently transferred through the networks. Phone audio is normally extremely compressed. So called HD Audio, audio with a wider bandwidth, was actually touted as great new iPhone 5 feature, since we've all noticed that the audio quality of cell phones calls are horrible compared to the real voice or even audio recordings made by the same microphones. VoLTE is a new technology and isn't totally ready yet, but when it is it'll enable vastly improved call quality. http://www.engadget.com/2012/02/24/fraunhofer-full-hd-voice-for-volte/ http://www.engadget.com/2012/02/24/fraunhofer-full-hd-voice-...

yardie 14y ago
Voice quality used to be very good on mobile. My first CDMA phone was indistinguishable from a landline, with some people surprised I was right outside their door when I called. And it was a big selling point in the early mobile analog to digital transition. My first cellphone was from Primeco PCS who made had no qualms about saying that TDMA (the competing standard at the time) sounded like shit compared to their CDMA phones. As all good things eventually end Primeco was sliced up into Verizon Wireless and Sprint. With the only competing tech being TDMA from ATT Wireless they compressed the voice channel even more to accomodate more customers. TL;DR: CDMA audio, currently, is almost indistinguishable from landlines but the carriers choose compression over quality
- seiji 14y ago
  Quite true. On my old Verizon Motorola P8767 (a color flip phone -- it had four colors) I could enter "engineering mode" and increase the bitrate of voice calls over the network. It meant you were using more than your share of the voice pipe, but at least my voice sounded excellent. Switching to a 2007 AT&T iPhone from Verizon was the equivalent of going back to two tin cans on a string. A string that a vengeful voice god would cut at random between 5 and 15 minutes every call.
- plorkyeran 14y ago
  "Indistinguishable from a a landline" is a pretty low standard. Landlines have terrible quality compared to nearly every VoIP system I've used.
  - apendleton 14y ago
    Yes, was about to respond and say exactly this. The frequency response is something like 300-3500Hz (vs. 20Hz to 20kHz for normal human hearing), and the dynamic range is also pretty mediocre. Skype is much better, and many in-network cell calls that never touch POTS also have better call quality already than landline phones do.
  - yardie 14y ago
    Yes, now imagine a mobile phone system with quality that couldn't even match that. People can usually tell you are calling from a mobile based on the quality of the call. Skype is great, until about 1800-2000h. Then the quality turns to crap as everyone comes home, does netflix, bittorrent, youtube, etc. and saturates the bandwidth. Unlike most offices, homes don't get a SLA.
- jjtheblunt 14y ago
  You're absolutely right. They chose compression over quality to load as many concurrent calls per tower (CDMA, mind you) as tolerable. It used to be (maybe still is) that on the Motorola Razr v3m you could drop into a programming menu, and force the handset to use the higher bitrate vocoder, whereas the towers would request use of the lower bitrate vocoder. Around Chicago, in 2000, for example, Sprint CDMA was indistinguishable from a landline, likely because the towers were telling handsets to encode with the high bitrate.
yaantc 14y ago
"Enable" is indeed the key word. VoLTE does support AMR wideband, and there are other wideband codec evolutions in the pipe. But it also supports AMR narrowband. So it'll be up to the operator to decide between higher voice quality or higher capacity. That will depend on how much spectrum is available, and load. It may even change during the day depending on a cell load.
seanalltogether 14y ago
I've always found Skypes audio quality to be far superior to phone or cellphone...that is when lag doesn't come into play. I wonder how much more or less bandwidth they use for audio vs traditional voice networks.

yardie 14y ago

Voice quality used to be very good on mobile. My first CDMA phone was indistinguishable from a landline, with some people surprised I was right outside their door when I called. And it was a big selling point in the early mobile analog to digital transition. My first cellphone was from Primeco PCS who made had no qualms about saying that TDMA (the competing standard at the time) sounded like shit compared to their CDMA phones. As all good things eventually end Primeco was sliced up into Verizon Wireless and Sprint. With the only competing tech being TDMA from ATT Wireless they compressed the voice channel even more to accomodate more customers. TL;DR: CDMA audio, currently, is almost indistinguishable from landlines but the carriers choose compression over quality

seiji 14y ago
Quite true. On my old Verizon Motorola P8767 (a color flip phone -- it had four colors) I could enter "engineering mode" and increase the bitrate of voice calls over the network. It meant you were using more than your share of the voice pipe, but at least my voice sounded excellent. Switching to a 2007 AT&T iPhone from Verizon was the equivalent of going back to two tin cans on a string. A string that a vengeful voice god would cut at random between 5 and 15 minutes every call.
plorkyeran 14y ago
"Indistinguishable from a a landline" is a pretty low standard. Landlines have terrible quality compared to nearly every VoIP system I've used.
- apendleton 14y ago
  Yes, was about to respond and say exactly this. The frequency response is something like 300-3500Hz (vs. 20Hz to 20kHz for normal human hearing), and the dynamic range is also pretty mediocre. Skype is much better, and many in-network cell calls that never touch POTS also have better call quality already than landline phones do.
- yardie 14y ago
  Yes, now imagine a mobile phone system with quality that couldn't even match that. People can usually tell you are calling from a mobile based on the quality of the call. Skype is great, until about 1800-2000h. Then the quality turns to crap as everyone comes home, does netflix, bittorrent, youtube, etc. and saturates the bandwidth. Unlike most offices, homes don't get a SLA.
jjtheblunt 14y ago
You're absolutely right. They chose compression over quality to load as many concurrent calls per tower (CDMA, mind you) as tolerable. It used to be (maybe still is) that on the Motorola Razr v3m you could drop into a programming menu, and force the handset to use the higher bitrate vocoder, whereas the towers would request use of the lower bitrate vocoder. Around Chicago, in 2000, for example, Sprint CDMA was indistinguishable from a landline, likely because the towers were telling handsets to encode with the high bitrate.

yaantc 14y ago

"Enable" is indeed the key word. VoLTE does support AMR wideband, and there are other wideband codec evolutions in the pipe. But it also supports AMR narrowband. So it'll be up to the operator to decide between higher voice quality or higher capacity. That will depend on how much spectrum is available, and load. It may even change during the day depending on a cell load.

seanalltogether 14y ago

I've always found Skypes audio quality to be far superior to phone or cellphone...that is when lag doesn't come into play. I wonder how much more or less bandwidth they use for audio vs traditional voice networks.