We’ve long been wary of metal iPhone cases and their signal-killing tendencies. Yet companies must still see some demand for such accessories, since Luxa2 has just unveiled Alum X for iPhone 4/4S ($60). Made of — you guessed it — brushed aluminum, this one’s a two-piece case with a bumper that fits around the iPhone’s antenna and interchangeable backplates. Luxa2 claims cutouts around the antenna breaks will help maintain signal strength; we put it to the test and found the results to be mixed. Alum X comes in red, silver, and dark grey.
To prevent the metal case from scratching the iPhone’s body, the interior is lined with a thin pieces of foam.
There’s still a bit of rubbing between the two hard surfaces where there are gaps in the material, but we never saw any scuffs or marks on the device. You then have the option of sliding one of two backplates: one with full coverage save for a hole around the Apple logo, or the other that simply acts as a frame and leaves most of the glass back exposed. Of the two we prefer the more protective one for obvious reasons, but cite Luxa2 for leaving the logo open. The aluminum is thick enough to make pressing the iPhone’s buttons a little tougher, but doesn’t prevent it from making an electronic connection in Universal Docks. Larger than average Dock Connector plugs won’t fit, however.
We tested Alum X in a number of locations to see if it had any effect on reception.
Our results were mixed, but generally there was at least a small amount of attenuation. Cellular service sometimes dropped by as much as two bars, while the Wi-Fi signal would often drop by one in areas where it was otherwise full. Compared to some other cases we’ve tested these results aren’t terrible, but they could end up negatively affecting the use of your iPhone.
Metal cases have never really appealed to us, and this one’s no exception. It adds weight to the device without offering the same sort of shock absorption that a rubber and plastic case might. Add in the reception issues, as small as they may be, and this case certainly isn’t for everyone.
