Though they don’t require lengthy reviews to explain, iPhone headphone port adapters are a necessity for fans of earphones or headphones that pre-date Apple’s mid-2007 mobile phone: the recessed headphone port requires either an especially small, thin plug or an adapter with such a plug at one end, and an open 3.5mm port at the other. Many companies have released these sorts of adapters; today we look at options from DLO and ifrogz.

DLO is actually selling two different options: the Headphone Adapter for iPhone ($10) and the Headphone Splitter ($15), each with a clean, almost entirely black plastic design. Whereas the 4.5-inch-long Headphone Adapter does nothing more than provide a way for you to connect one pre-iPhone headphone plug to the device’s recessed, thin headphone port, the six-inch corded Headphone Splitter lets you connect two plugs to the iPhone at once.
But that’s not all.
Both of these cables use three-pin headphone port connectors, which some might see as overkill in the Headphone Adapter: relatively few 3.5mm stereo headsets existed prior to the iPhone, even fewer of which iPhone users would care about. But in the Headphone Splitter, this feature makes more sense, since unlike any other splitter we’ve seen, DLO’s includes one port with the ability to pass through iPhone-specific microphone and remote functionality, while the other port is designed for standard mic-less headphones. Put another way, Headphone Splitter’s the only one we’ve seen that lets one person plug in a standard iPhone headset to listen and/or talk while another person uses standard iPod earphones to listen.
DLO competes in the iPhone adapter and splitter markets with a number of other companies, most notably Griffin, which sells a $10 adapter and $15 splitter with integrated volume controls, and Monster, which sells a $20 splitter with volume controls and a mute function.
The advantage of volume controlled splitters is apparent only when you’ve used them: if you’re using different types of earphones, one’s likely to be louder than the other, and the in-line volume controls let you remedy this.
By comparison with these options, DLO’s standard adapter isn’t especially distinctive or uniquely cheap—ifrogz’ functionally identical Fitz strikes us as a better deal—and though its splitter’s mic pass through functionality is nice, we tend to prefer the independent volume control features found in its competitors. Pick the Headphone Splitter if you really have a need for pass-through iPhone mic and control functionality while you’re sharing the headphone port, and don’t mind losing its competitors’ independent volume controls in the process.
Our Rating
Company and Price
Company: Digital Lifestyle Outfitters (DLO)
Website: www.DLO.com
Model: Headphone Adapter
Price: $10
Compatible: All iPods, iPhone
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