The biggest development in the world of portable digital audio in the 21st century has undoubtedly been the iPod, and car stereo makers have come up with innumerable ways to let drivers play their iPod libraries on the road.
Auxiliary-input jacks
The most basic solution for in-car iPod playback is a generic line-in jack and patch cord, which enables drivers to stream music from their players via the stereo to the car's speakers. Some stereos, such as the Sony MEX-BT2500, have auxiliary-input jacks built in to the front of their faceplates to enable drivers to play content from iPods, Zunes, and other digital-audio players through the car speakers.
When playing audio via an aux-input jack, drivers are still required to use the digital-audio player itself to select and control all music playback. The same is true for connections made via FM transmitters, which plug directly into the player and broadcast the iPod's audio to the stereo, and for old-school cassette adapters.
Single-DIN systems
For those looking for a greater degree of control over their iPod libraries when behind the wheel, there are a wealth of stereos that feature an "intelligent" or "full-speed" USB iPod connection, which transfers information from the iPod to the stereo's display itself and gives the driver full search and playback control via the stereo's faceplate buttons. Technically, USB-compatible systems will produce a better sound quality than auxiliary-input jacks because there are fewer connections on the way to the speakers. Stereos with a USB connector let you plug in a USB key filled with MP3 files, and the stereo will use the key as an audio source, just like a CD. With an auxiliary input, you are playing the music on your MP3 player, then running its output into the stereo, where it gets amplified again, as opposed to the single amplification step with the USB key. In reality, you probably won't notice a difference in audio quality, because it will be minimal.
The challenge for single-DIN stereos with intelligent iPod connections is to present a user-friendly means of navigating iPod libraries. Single-DIN stereos don't have the luxury of touch screen systems found in many double-DIN systems, and so, as with MP3 discs, the presentation and navigation interface for iPod tracks is a critical factor in their usability.
Sony's CDX-GT610UI
Among the single-DIN-size stereos that we have seen that do a reasonable job of transferring iPod control to the driver are the JVC KD-PDR30, which all come with iPod connections as standard. With the Sony CDX-GT620IP, for example, drivers can select songs according to artist, album, or playlist. In iPod mode, the stereo's single-line LCD display shows information on artist and album, track name, or track number, according to the user's preference. Although the display shows only eight characters of each information tag, a dedicated SCRL button scrolls the information, enabling the curious driver to get all the relevant information. An option in the setup menu also enables users to configure the display to automatically scroll tag information when a new source, album, or track is selected.
If iPod connectivity is your priority, however, then there is one system that stands head-and-shoulders above the competition in the single-DIN category. The Alpine iDA-X001, designed with input from Apple, is a dedicated in-car iPod interface. Not only does it have a wheel that mimics the movements of the iPod controller, but it also provides menus in the same fonts as the iPod itself, and even displays album art for tracks on fifth-generation iPods.
The iDA-X001 is the first car stereo we have seen that has no internal moving parts. The single-DIN-size stereo comes with a range of features that gives drivers direct control over the songs in their iPod libraries, including a spring-loaded jog wheel for browsing through iPod libraries; an alphabet search function inspired by newer iPods; and a bright, 320x240-pixel TFT screen for displaying album art and iPod menus.
Touch screen systems
For systems with touch screen LCD display, recreating the iPod experience is easier, and many double-DIN-size stereos feature a virtual version of the iPod wheel or the iPod screen itself. However, more real estate does not necessarily mean a more user-friendly iPod experience. When evaluating the usefulness of these touch screen iPod interfaces, one of the important factors to consider is ease of scrolling through digital-audio libraries: if you have an 80GB iPod connected, then you will not want a system that requires you to search through songs one--or even six--at a time.
The Dual XDVD8182 and the Pioneer AVIC-Z1 are examples of systems with cumbersome and labor-intensive iPod interfaces.
Searching through iPod tracks on the Dual XDVD8182 can take forever.
When using the Dual XDVD8182's touch screen to navigate iPod libraries, for example, the only way to browse tracks is by pushing the up or down arrows (to see each name one at a time) or by pressing the File button that allows you to skip forward six entries at a time. As an example of how time-consuming this method of browsing is, it took us more than 120 presses of the File buttons to get through the list of artists in our 4GB iPod Nano. As with the Dual system, the Pioneer AVIC-Z1 only allows users to scroll through iPod entries five at a time; with 80GB of songs loaded on an iPod, getting to the bottom of the list will take hours.
Systems that do a good job of reproducing the iPod interface retain the simplicity of the player itself and give users a means of quickly navigating large libraries. Two such systems we have seen are the Alpine IVA-W200 and the Clarion MAX675VD./p>
The IVA-W200 does a good job of offering a flexible range of control options for iPod music: users can select tracks by the artist, the song title, the album, or the playlist. The IVA-W200 screen displays full tag information for each track, and its basic text format and lack of fancy graphics enable drivers to read the information at a glance. To get through large iPod libraries, the IVA-W200 features a touchable search bar, which enables drivers to quickly skip through the alphabetized list of tracks or artists.
With the Clarion system, drivers are presented with an iPod dashboard on the system's bright LCD touch screen display, from where they can select tracks according to the usual iPod categories (podcast, artist, album, playlists, genres), and can search within those categories. Like the Alpine IVA-W200, the system has a user-friendly one-touch scrolling feature for searching large music libraries.
