The iPhone and iPhone 3G have different earphone ports. Sennheiser and a few other manufacturers, notably V-Moda and M-Jay, were quick off the mark and produced earphone headsets that have slim jacks and work with both types of iPhone.
The Sennheiser MM50 IP is the company's first effort for the iPhone, but the company has long been making headset and earphones and has won awards from us before.
The packaging promises sound isolation, which is achieved by a tight fit between the rubber earcups and your ear canal. The MM50 has a short, shallow shape in the ear and loose rubber cup, but both elements failed to isolate sound properly in our view. We also found that the earpieces could sometimes slip out of the ear, especially with a quick turn of the head.
Despite the lack of sound isolation, which is an overhyped feature on earphones these days, the sound quality is well balanced from the MM50 IP. The mid frequencies are well presented across the board, which means they display voices well too, and although during music playback the bass could sometime intrude, the overall sound is extremely engaging.
The positioning of the mic was a little too low on the cable for us. We like to tuck the dangling cable inside the coat or jumper, but found the mic often caught on our collar. People we called mentioned they could hear the muffled noises of the mic catching. If you don't mind bending the cable so that it loops slightly, you'll be fine.
The low price of the set is probably its biggest plus. You get more than enough sound quality for your buck, especially considering competitors from vModa and Etymotic can run over £100.