The digital transition that promised us better call quality and fewer dropped calls was an advertising sham. In reality, digital only enabled AT&T to cram more calls onto already-crowded frequencies – sacrificing call-quality for profitability.
In an effort to cram as many calls as they can into their antiquated, and poorly tuned network, AT&T uses extreme levels of voice compression. The result is, instead of intelligible human sounds on AT&T, you hear garbled, phasey, gasps of conversation – until AT&T chooses to drop your call.
To be fair, compression schemes are the backbone of the digital age, and can be of huge benefit when used properly. AT&T DOESN’T. Instead, to maximize profit, they’ve turned the quality knob to ‘low’ in many markets – most notably Austin. Why? Because they can. The more users they can cram onto a frequency and cell tower – the better it is for their bottom line.
AT&T uses GSM/TDMA multiplexing to broadcast voice traffic. In a silver of time, your voice data plays musical chairs with other calls sharing the same frequency. Because your call is broadcast as brief burps of data — a few missed snippets and important words just fade away like they never happened.
But wait — it gets worse. Then, to pack calls even tighter, AT&T uses AMR [Adaptive Multiple Rate] compression on your voice. Other carriers allow the use of FR [full-rate] and EFR [enhanced full-rate] varieties of AMR to protect voice quality. AT&T doesn’t, at least for iPhone users. In most every market, AT&T locks iPhone users to the audibly inferior HF [half-rate] compression. Why?
The reasons cited in AT&T forums and technical journals are many: lack of back-haul capacity, lack of cell towers and bandwidth, and the iPhone’s greater demand for data services, are all offered as excuses. The fact remains that iPhone users are not getting the voice quality we contracted for — and pay for every month.
AT&T’s recent meltown during SXSW was a good example. Even marginal voice-quality evaporated, then crashed, leaving thousands of iPhone users stranded, until they belatedly hauled in portable cell sites [COWS - cellular on wheels] to pick up the load. Only when the SXSW management shamed AT&T in front of national media did they move to -temporarily- improve their network.
AT&T has the technology to do better. AT&T Voice Quality Lab in Middletown, NJ explores and tests next-generation technologies. So, you might correctly ask – why can’t they deliver clearer, more reliable voice quality? I suspect because not enough of us have demanded the quality we pay for.
iPhone users deserve better than AT&T. What do you think?
NOTE: Opinions expressed herein do not necessarily reflect the opinions of CapMac, it’s Board, or it’s members.