T-Mobile launches HD Voice

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wirednuts

Diamond Member
Jan 26, 2007
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I do. I'd like to hear what hardware and software is actually required to do it.

mee too. and id like to know what the actual bandwidth ranges are. i think right now voice calls are set to what they were in analog pots days- which is a spectrum based on some military research for optimal vocal quality in the smallest frame of hz. something like 600-3000 i think... i could be way off i dont remember.

i would imagine the HD range goes a lot higher, making it much easier to understand what the hell people are saying. i really wonder if it adds low end, because thats where you lose the most efficiency causing high data flow rates...
 

wirednuts

Diamond Member
Jan 26, 2007
7,121
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ok its in the pudding-

HD Voice enables calls with a much wider dynamic range. AMR-WB is a direct successor to AMR-NB (narrowband) and offers higher frequency bandwidth of up to about 8 kHz (16 kHz sampling) as opposed to AMR-NB's 4 kHz. I'm unclear what bitrate or coding mode T-Mobile US is using, however I'd be willing to suspect that T-Mobile has probably gone for enabling the full AMR-WB range of bitrates. I have to say I'm impressed with T-Mobile US' constant leadership over AT&T with UMTS upgrades in the US. AT&T currently runs AMR-NB at 5.9 kbps for comparison, not even the full allocation AMR-NB bitrate. Update: It's possible that T-Mobile is using the 12.65 kbps AMR-WB bitrate.


http://www.anandtech.com/show/6594/tmobile-announces-amrwb-hd-voice-calls-active-on-its-network


so it is higher khz on the high end, but no notes about lower frequencies... which i assume arent changed then. no reason to i guess, its not like our phones have beats audio in them or anything LOLOLOZ