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As bandwidth grows, cell phone audio improving

‘Hello,” said my real estate broker’s voice on the telephone, and I jerked upright in my chair. I couldn’t quite believe what I’d just heard.

“Do you hear that?” I said.

“Yeah,” he replied. “It’s amazing.”

What each of us heard was the other person’s voice, sounding remarkably rich and full. It was as though the speaker was standing beside me, not miles away and talking through an iPhone 6. For a little while, we forgot all about real estate.

Remember when you first saw a high-definition TV set and couldn’t stop talking about it? Hearing clear, crisp speech over a cellphone delivered the same delicious shock. Soon I was roaming the newsroom, waving my iPhone at people and telling them the future had finally arrived.


After years of talking about it, the major cellphone carriers are introducing a technology called HD Voice that will bring traditional telephone calls into the 21st century.

If you’re using compatible phones on a compatible network, you can already hear the difference. And someday soon, we all will.

HD Voice answers a question that’s nagged at me for years: Why do phone calls sound so bad?

Not just cellphone calls — all calls. Telephone audio quality has barely improved in 50 years. The TV sets of my childhood had a single tinny speaker, 3 inches across. Today, we get surround sound. Early computers merely beeped at us. Today, they’ll play you an opera.

But landline phone calls sound as cheesy as ever, and cell calls are worse.

Blame it on bandwidth, or the lack thereof.

The copper wires used in old-school telephones can’t handle much data. So engineers designed them to transmit only a sliver of the frequencies that can be detected by the human ear. As a result, subtle nuances of speech are lost. That’s why you have to ask callers to spell words beginning with the letters “s” and “f”. On the phone, you can barely tell the two apart.


When cellphones came along, they stuck to the same voice-quality standard, and with good reason. Bandwidth on early cell networks was even more scarce than for landlines. Factor in the inevitable problems with radio reception and cellphones became notorious for lousy sound quality.

But with enough bandwidth, phone calls can sound superb. Fans of Internet calling software, such as Microsoft’s Skype, already know this. When two computers connect over Skype, the call comes through with rich, deep audio.

And in recent years, wireless phone networks have gotten a bandwidth boost through the LTE wireless technology now deployed by all major cell carriers. These networks can handle millions of data bits per second, per phone.

First-generation LTE systems still handle voice calls through a separate network with restricted bandwidth. You could make HD Voice calls through separate apps such as Skype or the iPhone’s FaceTime Audio app, but only to other users of these apps. But now carriers are switching to a new system called VoLTE — Voice over LTE — that transmits voice calls over the phone’s data connection.

With VoLTE, subscribers to Verizon Wireless and Sprint will finally be able to make phone calls and surf the Internet at the same time, a feature AT&T and T-Mobile have offered for years. And all VoLTE phones will get an audio upgrade.


The latest smartphones, including the iPhone 6, the HTC One, and the Samsung Galaxy S5 and S6, can transmit more than twice the sound frequencies of traditional phones. Calls on these phones don’t just sound as good as landline calls— they sound better.

“You will finally be able to hear that very famous pin drop that Sprint made famous,” said Jeff Pulver, an Internet telephone entrepreneur and early proponent of HD Voice.

My wife couldn’t find a pin to reenact those old Sprint TV commercials, so she dropped a small paper clip close to an HD Voice-compatible phone borrowed from Verizon Wireless. The sound came through loud and clear on my Verizon test phone, located miles away. When we tried it with a standard cellphone, the sound was barely audible.

Both of us used Verizon phones because for now, every cell company’s HD Voice service only works on its own network. An AT&T phone can’t make an HD Voice call to a Verizon phone, for instance. But that will soon change. The major carriers are in talks to make their voice upgrades universally compatible.

In most cases, HD Voice just works whenever you call a compatible phone. With some phones — the iPhone 6 on Verizon Wireless, for instance — the feature must be manually switched on. Your carrier can tell you exactly how.

Other problems: Some carriers have not yet activated HD Voice in some parts of the United States. And those with older, incompatible handsets are out of luck until they upgrade.


So it could be months or even years before all of us get an earful of HD Voice. But prepare to be very pleasantly surprised.

Hiawatha Bray can be reached at hiawatha.bray@globe.com. Follow him on Twitter @GlobeTechLab.