As you most likely know already, Apple’s iPhone has a recessed headphone port, sunk several millimeters below the rest of its metal top surface. Consequently, if you own pre-iPhone earphones made by any company except Apple, there’s a very good chance that they won’t physically connect to the iPhone, so you have two options: buy new earphones, or buy an adapter. We’ve previously reviewed a number of different adapter options, including Griffin’s Headphone Adapter for iPhone, Belkin’s Headphone Adapter for iPhone, Monster Cable’s iSplitter 200 Headphone Jack Splitter, Griffin’s SmartShare Headphone Splitter, and RadTech’s ProCable Stereo Audio Extender for iPhone. All of these accessories fit iPhone’s headphone port and enable you to connect your favorite old earphones without a hassle. But what are you supposed to do when a phone call comes in?
Shure’s Music Phone Adapter MPA-3c ($40) is the only adapter of the bunch to take a bigger-picture approach to iPhone headphone port modification. Rather than just connecting your old earphones to the iPhone, MPA-3c adds to them an in-line microphone and control button box, which is found at one end of its cable. In so doing, it converts your earphones into a complete alternative to the iPhone Stereo Headset included by Apple in every iPhone box, capable of interrupting audio immediately to handle phone calls.
Because the microphone needs to be near your mouth, Shure’s extension cable is nearly three feet long—six or seven times longer than the ones in other adapters—and includes a lapel clip to keep the microphone at neck level. It’s best suited to earphones, such as Shure’s, that split off at around your neck level into two separate cables.
Our photographs here show MPA-3c with Shure’s SE210 and SE530 earphone models, neither of which is included; our reviews section highlights many other earphone options. With such earphones, you disconnect half the cable, put it away, and replace it with the MPA-3c; the length and fit are perfect, even without using the lapel clip. You’re now microphone-equipped and ready to go.
When we tested a near-final prototype of the MPA-3c, callers could hardly tell the difference between Shure’s microphone and the one in Apple’s iPhone Stereo Headset. But in our more complete testing of the final production version of the MPA-3c—currently available only in very limited quantities—we found Shure’s microphone to have certain decided advantages and disadvantages relative to Apple’s.
Shure accurately claims that its microphone system enhances “intelligibility regardless of background noise;” our callers said that a slight treble boost made our voices sound easier to understand, relative to the warmer, less crisp sound of Apple’s Headset.
However, they differed on whether they preferred the MPA-3c’s sound to that of the Stereo Headset, as all three callers noted that they could hear significantly more background noise with Shure’s more sensitive microphone, which Apple’s screened out. Two of the callers said that they could hear everything—footsteps, opening and closing cabinets, television sounds, etcetera—going on around us, whereas the same sounds were either much less obvious or entirely absent when using Apple’s free headset. Our third caller felt that the crisper, more intelligible voice made up for the additional background noise MPA-3c introduced.
Shure also includes a silver button on back to let you do the same things the iPhone Stereo Headset’s button can do, namely take or end calls, play or pause music, and skip forward one track at a time with a double button press. The button works exactly as expected: single clicks start or finish calls, and switch between paused and playing modes for audio. Quick double-clicks skip forward a track in the current collection of playing songs. The bulbous button box on MPA-3c is easier to click than the neat but small version on Apple’s Headset.
Our overall impression of MPA-3c was positive, but with certain caveats. While the Adapter is the first of its kind for the iPhone and unquestionably useful for those who want to add microphone and limited remote control features to certain prior premium headsets, proper mic sensitivity, positioning, and noise filtering remain tricky, and Shure has delivered an option that’s good but not amazing in most regards.