Sony CDX GT620IP - radio / CD / MP3 player

Standing on the shoulders of the entry-level Sony CDX-GT420IP, the CDX-GT620IP delivers as-standard iPod connectivity with some stylish and useful faceplate controls, including a dedicated browser interface for digital media libraries. With the ability to play a range of digital-audio discs, an aux-input jack, and some advanced audio tweaking capabilities, the CDX-GT620IP is a competitive option in the $160 range.

Design
The CDX-GT620IP is Sony's mid-level iPod-compatible car stereo. With a dedicated browse function for searching digital audio libraries, it sets itself apart from the CDX-GT420IP that we reviewed last year, while its basic two-line LCD and its lack of HD Radio compatibility position it below the top-end CDX-GT820IP. The layout of the faceplate is standard, simple Sony design: six primary control buttons surround the rotary volume/ feature-select dial, while six radio preset buttons along the bottom of the display double as control buttons for controlling and viewing digital-audio output. The neon blue or red backlighting for the main buttons and rotary dial has an element of vodka-bar cool but may jar with some car interiors. While its monochrome display is basic, we are impressed with its visibility--even in direct sunlight--as well as its basic but intuitive three-band graphic equalizer. A larger dynamic graphical representation of the audio output to the left of the EQ icon gives the stereo some life, but can make the display look cluttered when the second line is full of text.

Features and performance
As denoted in its "IP" designation, the CDX-GT620IP has an as-standard full-speed iPod connector, which transfers all controls of a connected iPod to the stereo faceplate. Unlike the entry-level CDX-GT420IP, the stereo has a one-touch interface for accessing iPod libraries. To browse tracks on the iPod, drivers press the Browse button denoted by a magnifying glass. The backlighting on the rotary dial flashes a neon blue (it can also be changed to red if that fits your car's interior better), indicating that it is the controller that is used to scroll through the iPod-related categories (Artist, Album, Genre, Playlist) that show up on the bluish-white dot-matrix display. The rotary dial has a solid, tactile feel and is calibrated to let drivers search through long lists of alphabetized entries reasonably quickly. Although with very long lists of tracks, you may find yourself turning the dial for quite some time before reaching Ziggy Stardust. Having reached the chosen category, drivers push the dial in, which brings up all the listings in that category.

The CDX-GT620IP's monochrome display shows up to 10 characters for iPod track information.

The stereo displays around 10 characters at a time, which is enough information to identify most tracks. One thing that we particularly like about these Sony systems is the dedicated Back button, which gives drivers the chance to back up one level rather than having to start a search over again if they go down a selection path they don't like. Dual-purpose preset buttons for repeat and shuffle (either track or album), and album-skip give drivers more options for controlling iPod output. Despite what it says on Sony's Web site, it appears that the CDX-GT620IP does not have the Jump Mode feature that lets users use the six preset buttons to skip to corresponding segments of a list of audio files on an iPod. This is disappointing, especially considering that the comparably priced Alpine CDE-9874 does come with a similar feature. (The flagship Sony CDX-GT820IP does come with Jump Mode, but will set you back another $70 or so.)

In addition to its iPod compatibility, the CDX_GT620IP can play the usual range of disc-based digital-audio formats including MP3, WMA, and AAC. The selection procedure for tracks on these discs also involves the Browser button. Unlike iPod tracks, the music on MP3 discs can only be searched in folder/file structure, which limits the navigability of large audio libraries on homemade discs; however, the DISP/Preset 6 button can be used to cycle though information on album, track, and ID3 tags. A front-mounted auxiliary input jack is a useful means of connecting any non-iPod portable audio players.

The CDX-GT620IP also differentiates itself from its entry-level sibling with some impressive audio-tweaking features. In addition to its seven EQ presets and three-band graphical equalizer, the stereo features Sony's digital soundstage optimizer, which enhances audio output by creating what Sony calls a "more ambient sound field." In practice, DSO delivers a mixture of increased volume and sharpened output. Aside from a universal increase in volume, the effect of the DSO is different depending on what kind of media is being played: with compressed audio files such as those on an iPod or an MP3 disc, the DSO appears to boost high- and mid-range output, leading to greater definition in vocals, snare drums, and cymbals.

The digital soundstage optimizer swells audio output.

With uncompressed Red Book CDs, the DSO feature has less of an immediate effect at its lowest setting, but at DSO 2 and 3 the effect is noticeable, particularly with low-end output as bass is enhanced, giving the impression of a low-output subwoofer. In all cases, the DSO has the effect of swelling the sound higher into the car's cabin, and comparison between no DSO enhancement and the DSO 3 setting is similar to the difference between listening to audio through a closed door and then opening that door to hear it unimpeded.

Being a member of Sony's Xplod lineup of car stereos, the CDX-GT620IP advertises its "100dB+" capabilities on the front of its faceplate, and thanks to its built-in 17-watt (RMS) amplifier, the system lives up to its promise with reasonably clear output even at high volumes. Those who want even more power have options to hook their own external amps and subs up to the CDX-GT620IP via three preamp outputs, including a dedicated sub preamp output with its own crossover and level control.

In sum
With an price of about $160, the CDX-GT620IP delivers decent sound quality and iPod compatibility for a competitive price. We like its stylishly simple faceplate design and its intuitive audio-search interface, while its DSO function gives even stock speakers a boost.