Back in December 2006, Playlist magazine ran a story stating that some 60 percent of 2007 model-year vehicles sold in the US featured at least an auxiliary input allowing iPods to be played through the car stereo. With that in mind, all those iPod listeners spending hours a day in their cars would need some way to keep the iPod juiced and ready to go.

Just your typical generic shot of the SmartCharge.

Enter the various car chargers, of which perhaps the most elegant-looking is SendStation’s SmartCharge. The $25 power adapter includes a 12-volt plug and a special USB cable that taps into a Dock Connector-equipped iPod’s line-level output for a clean music signal. Second-generation iPod shuffle and third-generation iPod users need not apply, however; SendStation specifically excludes these models from the compatibility list.

The SmartCharge is adjustable for tilt, enabling it to fit into tighter spaces that other power adapters miss out on.

The SmartCharge does a fine job of charging the iPod and a fine job of feeding the stereo a clean signal from the iPod’s output, but could not do both at the same time in any vehicle-cable combination tested. Playing music while charging the iPod results in a variable high-pitched whine and static through the stereo, which makes listening to the music nearly impossible. To this writer’s ear, it sounds like there’s a bad ground somewhere, which is why multiple vehicles and cables were tested (all with identical results). SendStation’s technical support team concurs with this assessment:

What you describe clearly seems to be a grounding issue, which is beyond our control. Unfortunately some cars have that, others don’t.

I’d be willing to accept this explanation had I tested exclusively in older cars or cars with aftermarket stereo systems that weren’t installed by a professional, but one of the test vehicles was my brand-new 2007 Mazda 3 with its factory stereo, a combination that seems like it ought to be free of any odd “grounding issues.”

The Mazda 3 has an ideally designed center console that allows for a clean hookup with the SmartCharge Dock connector in a compartment sized just right for iPods.

It’s a shame, really, because there isn’t a whole lot to the device, and it’s about as nice-looking as something that shoves into a cigarette lighter plug can be. Without any way to know ahead of time if your vehicle is one of the ones that has a “grounding issue”—and without any way to know whether or not the “grounding issue” can be fixed by a mechanic—it’s pretty difficult to give the SmartCharge a positive recommendation.

That center console also includes a 12V power plug and the auxiliary input jack, shown to the right of the SmartCharge.

Copyright © 2007 Chris Lawson. Reviewing in ATPM is open to anyone. If you’re interested, write to us at reviews@atpm.com.