14 DAY TRIAL // The first thing that catches the eye about Apple's iPhone is the multi-touch driven interface and the big display. Of course, it's the user interface and interaction that sets the iPhone apart from competitors, but there's more to the device than that. WirelessInfo has taken Apple's latest and have tested it thoroughly to see just how it performs as a cell phone, where sound quality is paramount.
To test the quality of calls made with the iPhone, WirelessInfo used professional testing equipment; a HATS (Head and Torso Simulator) that simulates the human head and ear and an electro-acoustic analysis program called SoundCheck. This allowed them to accurately analyze the quality of the sound that the iPhone sends and receives.
Sound Receive Frequency Response: This test measures the frequency response of sound the iPhone receives when it is used as a handset. This represents what someone talking to you over the phone sounds like. iPhone compares extremely well to other phones. The iPhone scores higher on this test than all of the five comparison phones, and only one phone that we have tested so far (the BlackBerry Curve) scored higher. Whatever Apple is doing with the small speaker inside the iPhone, they are doing it right.
Sound Send Frequency Response: Measures the sound that is being sent from rather than received by the phone. The iPhone's performance in this test was very good; the frequency response only touched against the limits a little. The bass response is perhaps a little higher than we like to see; this could make your voice sound a little bit bassier than it really is. But overall, the sound quality is very acceptable. It scored almost identically to the Treo 750, slightly higher than the Nokia N95, and much higher than the BlackBerry 8800.
Handset Side Tone: Side tone is how you hear your own voice when you are on the phone. So you can hear yourself speak, handsets inject a small amount of your captured voice back into the speaker. If they inject too much, your voice sounds too loud and you start whispering. Too much, and you start yelling. The ideal is about -18 decibels, but the iPhone seemed to have a problem here: we measured the side tone at -8.8 decibels. That's pretty high, so you might find yourself whispering a bit when you use the iPhone. This is comparable to the -9.43 decibels that we measured on the LG Prada, so it may have something to do with the thin, candybar style that the two share. However, nobody complained about how loudly we spoke on the test calls we made, so the low side tone may prove to be less of an issue than you might think.