The RDP-X50iP has all the hallmarks of a Sony product. The design is clean, modern, and restrained, using a mix of high-gloss black plastic across the top, matte black plastic around the back, and a satin-finish metal speaker grille on the front. Total dimensions are 6.5 inches tall, 14 inches wide, and 4.75 inches deep.
A traditional scooped universal iPod/iPhone dock cantilevers out from the front; it can be flipped up and out of the way when it isn't needed. The dock includes two plastic inserts that conform to the iPhone or iPod Touch, but they really aren't necessary unless you're a stickler for a snug fit. Since the dock conforms to Apple's universal standards, it accepts any insert you may already have for your iPhone or iPod.
The back of the RDP-X50iP is surprisingly bulky for a portable speaker system, compared with recent offerings from Altec Lansing and Logitech. If you're looking for loud, deep sound, though, it's easy to forgive the speaker's heft and thickness. A small recessed handle on the back helps with portability and also acts as a ported woofer. Below the handle you'll find the expected sockets for a 3.5mm aux input and a power adapter.
Another little feature we're happy with is the inclusion of a remote control. The remote has all the functionality found on the top of the RDP-X50iP. The range of the IR remote isn't great, but you can expect the typical 15- to 20-foot distance.
The RDP-X50iP is a testament to Sony's reputation for sonic innovation and sound quality. It's not the most balanced or restrained system, but if you want an impossibly big, rich sound from a compact system, the RDP-X50iP is tough to beat in this price range.
The RDP-X50iP's biggest sonic trick is its guttural low-frequency punch. Right out of the box, with EQ flat on our iPod, basslines and kick drums fill out the mix in a dramatic and unexpected way. We imagine that Sony engineers must have pulled this off using some creative speaker porting or a passive radiator, because the low-end sound has a similar acoustic quality to the Yamaha NX-B02 or the Kicker systems.