While smart phones continue to leap forward in most areas, from intuitive assistants and speedy data connections to dazzling displays and credible cameras, they seem to be mired in the mud when it comes to improving voice quality. Even the wall phone in grandma's kitchen probably sounds better than the smart phone in your pocket.
None of the 100-plus smart phones in our cell phone Ratings earned better than a good score for voice quality, and a significant number were only fair. By contrast, none of the cordless phones merited less than a very good, and a decent number delivered excellent voice quality. (Take a look at how Consumer Reports tests smart phone voice quality for more information.)
Still, it’s amazing that smart phones sound as good as they do when you consider the following:
1. They're space-challenged
When it comes to sound quality, cordless phones have it easy. They have only one primary function—voice calls—and their larger size lets them place their large microphones and speakers as close to your mouth and ear as possible.
Smart phones, on the other hand, are a technological sausage, densely packed with cameras, radios, microprocessors, sensors, and other hardware that enables them to do all those amazing things we expect them to do. Often, the tiny speaker is wedged between the bezel and the front-facing camera, while the microphone is sometimes relegated to the bottom of the phone—or the back. That almost guarantees a less-than-ideal connection with your mouth and ear.
2. The signals travel a long and winding road
Every second of a cellular voice call is a scientific miracle. What you say and hear is shredded into tiny pieces called packets that hitch a ride on microwave signals until they're reassembled by the phone of the person to whom you are speaking.
As those signals jump from cell tower to cell tower, they run into trees, mountains buildings, the weather, and other obstacles that cause them to split. The split signals produce a phenomenon called multipath, when multiple copies of the same signal reach your smart phone at different times, like an echo.
Deciphering multipath signals is quite difficult, and when the phone gets overwhelmed, the signal has to be retransmitted. Of course, few people notice because all of this happens within a fraction of a second. So that's why it's almost miraculous that voice calls sound as clear as they do.
3. They face a lot of competition
Part of a cell phone's appeal is that you can take them everywhere. Unfortunately everywhere is often a noisy place, filled with the din of traffic, rude conversations, and the sweet, distracting sounds of Mother Nature. Some phone makers brag about the noise-canceling technologies they've shoehorned into their devices, but they rarely make a significant difference, according to our tests.
So the bottom line is, don’t expect much, and be thankful for what you’ve got.
Next up, we'll provide you with tips on improving the voice quality of the phone you have in your hands now.
How Consumer Reports tests smart-phone voice quality
Consumer Reports' voice-quality tests are grueling. We put the phones in a special chamber that cuts them off from all external cellular signals so we can feed them our own. We mount the phone close to the "head" of a funky-looking machine called a head and torso simulator, or HATS—a sawed-off humanoid with a "mouth" and "ears"—that speaks on the phone and feeds what it says and hears to a computer for analysis.
We use recorded and simulated male and female voices, and those conversations take place in a wide range of simulated environments, ranging from the quiet indoors to noisy roadsides, complete with rumbling trucks.
The verdict: Voice quality averages out to good for most smart phones, with the quality of what you hear sounding slightly worse than how others hear you. That means when there's a lot of background noise, such as when you're on a busy street, expect to miss a word or two during the conversation.
Consumer Reports has no relationship with any advertisers or sponsors on this website. Copyright © 2006-2014 Consumers Union of U.S.