The overall footprint of the speaker dock is around 8 inches square, rising 3 inches high at its tallest point. At the top of the modern-looking heap, you'll find a clear plastic dock well that accepts universal inserts, including the matching clear plastic fitting that comes included. The system meets with Apple's "Made for iPhone" certification, so you can rest assured that your iPhone or iPod will charge, and that the speakers and wiring are shielded to prevent cellular interference.
On the back of the On Stage IV you'll find a power button, aux input, and a Mini-USB port for syncing your docked device to a computer. Flipping the On Stage over, you'll see a battery compartment for six AA batteries. JBL rates the On Stage IV at 16 hours of battery life, and uses a battery-preserving auto-shutoff feature after 5 minutes of continuous silence.
There are a total of four 1-inch JBL Odyssey speaker drivers embedded on the On Stage IV, grouped in pairs for the left and right. Unlike conventional stereo systems, the speakers all fire out at different angles in an attempt to spray the sound in all directions. As a spec, it's impressive to see four drivers on a product so small, but the real world payoff is negligible. Compared with similarly priced systems, such as the Logitech S715i, or the Altec Lansing inMotion Classic, the JBL On Stage IV lacks a little in both bass and clarity. As with many portable speakers we also found the character of the sound to be very dependent on volume level, requiring a moderate listening level to introduce the low end, but easily overdriving lower frequencies when too much gain is involved.
The On Stage IV redeems itself slightly with an included IR remote. The remote features controls for volume, tracks selection, and menu navigation. The remote is good for around 15 feet, but it's nothing spectacular.
The good news is that we've been flooded with surprisingly good-sounding compact iPod/iPhone systems recently, such as the Philips Fidelio, the Logitech S715i, and the Sony RDP-XF100iP. If you're not dazzled by the On Stage IV's design, these alternatives offer a better bang for the buck, and look pretty great in their own right.