Pros: iPod-matching headphone jack splitter lets you simultaneously use two sets of headphones or speakers with the iPod. Two free Audible audio programs (books/magazines) are included for free with each purchase – but this premium is the same as an offer currently advertised elsewhere for free.
Cons: Not as attractive as Macally’s functionally similar PodDuo, doesn’t include gold-plated contacts of Monster’s iSplitter, slightly pricier than both of those options.

Hot on the heels of our review of MacAlly’s PodDuo (iLounge rating: A-) comes an interesting competitor: XtremeMac now offers the iPod Audio Splitter ($12.95), which also splits the iPod’s single headphone port into two ports so multiple sets of headphones or external speakers can be used at once.
There are now at least three such accessories for the iPod – MacAlly’s, XtremeMac’s, and Monster’s earlier iSplitter. They all function identically, preserving audio quality while dividing the iPod’s headphone port into two, though there are a few aesthetic dissimilarities between the units, and XtremeMac’s Audio Splitter also offers an unexpected premium for buyers.*
Visually, the Audio Splitter fits in-between the PodDuo and Monster’s earlier iSplitter in iPod-appropriate design: it doesn’t dangle off the iPod like the iSplitter, but isn’t as squat as the PodDuo. Rather, the Audio Splitter sits atop an iPod like a small protruding glossy white nub, similar to Belkin’s earlier Universal Microphone Adapter in its design.
Its top surface is matte gray plastic, with no exterior metal contacts touching the headphone jacks.
XtremeMac’s design choices lead to the following assets: the Audio Splitter is quite compact and easy to travel with, moreso than the iSplitter, though not as attractive on the iPod’s top as the PodDuo. Like the Microphone Adapter, though, and unlike both the iSplitter and PodDuo, it has a plastic anchor nub that fits into the iPod’s four-pin extended headphone port, keeping the Audio Splitter from twisting around when it’s plugged in.
XtremeMac’s unit also places its two headphone ports pretty close to one another. Thankfully, the ports aren’t too close for normal pairs of iPod-compatible headphones, or the larger-jacked headphones we tested (and photographed for your reference) to peacefully co-exist, but audiophiles with oddly designed headphone jacks should take note: the Audio Splitter’s ports are millimeters closer together than the iSplitter’s and more than an inch closer than the PodDuo’s.
It’s also worth a brief mention that of the three products, only Monster’s iSplitter uses gold-plated contacts, a point that doesn’t matter all that much under most circumstances. But the Audio Splitter’s all-plastic exterior shell may help those looking to avoid metal-on-metal headphone jack contacts, a counterbalancing point in its favor.
[* = Updated December 31, 2004 @ 4:40PM:] In our original review of the Audio Splitter, we noted that the $12.95 peripheral’s only major advantage over its $9.95 competitors was XtremeMac’s inclusion of an unexpected premium – an Audible card entitling buyers to 2 free audio programs without having to pay $21.95 for an Audible membership. While the same deal isn’t available directly from Audible’s main page, users can get it without an Audio Splitter purchase just by clicking through Audible advertisements – including one in the iLounge forums. The original review pointed out that: “We’re not sure whether the Audible promotion will last for the duration of the Audio Splitter’s availability, but for so long as it does, the Audio Splitter will merit a high recommendation from us – especially for audio book lovers, it’s almost like getting a book and the Splitter free for the price of one book.