The Sony MEX-BT2500 features a simple, single-DIN-size faceplate with an open CD slot and a standard arrangement of hard buttons along the bottom of the bezel. To the left of the unit's white-on-black monochrome display, the rotary volume-knob doubles as a start/end call control, while six hard buttons surrounding it constitute the main control selections.
The MEX-BT2500 can be used to play regular CDs as well as discs encoded in the MP3 and WMA formats. When playing digital-audio discs, the monochrome LCD shows ID3 tag information for artist, album, and song title.
The system can be paired with as many as five cell phones simultaneously. One of the limitations of the MEX-BT2500's hands-free calling interface is that it cannot be used to place outgoing calls, other than redialing a connected cell phone's last number. We are also disappointed with the outgoing call quality via the system's built-in microphone.