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Audio mode, function - GF82.85-P-2030TXB

MODEL 211, 219 with CODE (527) COMAND APS with single DVD drive (with navigation) except CODE (498) Japan version except CODE (494) USA version as of model year 09/YoM 08 

General information 

The audio mode is made up of the following functions which can be activated using the Audio menu item:

A further function is described in a separate document:

Operating instructions 

Audio functions are operated using the following components:

Function requirements 

Function sequence for radio mode (FM/MW/LW/SW), in general 

The antennas in the rear window (model 211.0, 219) or in the side windows (model 211.2) receive high frequency (HF) signals for the radio-frequency bands frequency modulation (FM) and amplitude modulation (AM) (MW, LW, SW). The following useful signals relevant for the radio reception are modulated onto these HF signals:

The high frequency signals are routed via direct lines to the corresponding antenna amplifier. These antenna amplifiers filter the frequencies of the radio frequency bands out of the received HF signals and amplify them. The amplified signals are then sent over coaxial lines (FM, AM) to the tuner integrated into the COMAND operating, display and controller unit where they are demodulated.

The demodulated audio signals in vehicles with code (810) Sound system are routed from the COMAND operating, display and controller unit via the Media Oriented System Transport (MOST) to the sound system amplifier (N40/3) where they undergo final amplification. The audio is then output by the following speakers via direct lines:

IMPORTANT The audio signal for the bass box speaker travels from the COMAND operating, display and controller unit via MOST to the amplifier for sound system and from there, over direct lines via the subwoofer amplifier (N40/9) to the bass box speaker.

IMPORTANT For vehicles except code 810 Sound system, the audio signals undergo final amplification by the COMAND operating, display and controller unit and are then output over the following speakers via direct lines:

Function sequence for AM tuner (MW, LW, SW) 

For the MW and LW radio frequency bands, the useful signals are broadcast using amplitude modulation (AM). The AM tuner integrated into the COMAND operating, display and controller unit demodulates these signals. In other words, it separates the useful signals (audible frequencies) from the carrier signal (inaudible).

FM double tuner function sequence with phase diversity (FM) 

For the FM radio frequency band, the useful signals are broadcast using frequency modulation (FM). The FM double tuner integrated into the COMAND operating, display and controller unit demodulates these signals. In other words, it also separates the useful signals (audible frequencies) from the carrier signal (inaudible).

The COMAND operating, display and controller unit also performs changeovers depending on the reception quality.

Function requirements for Radio Data System (RDS) 

Function sequence for RDS 

Apart from the normal radio program, many radio stations (FM) transmit additional digital information such as station names, program type (PTY) (e.g. pop, culture, etc.) and traffic program identification. This information is evaluated by the COMAND operating, display and controller unit and appears on the display of the COMAND operating, display and controller unit:

Function sequence for media player 

A DVD drive is integrated into the COMAND operating, display and controller unit. This enables audio CDs or audio DVDs (including in MPEG-1 audio layer 3 (MP3) format) to be played. The integrated SD card reader enables music files in MP3 or Windows Media Audio (WMA) formats to be played or copied into the MUSIC REGISTER.

User navigation for controlling DVD/CD functionality and displaying supplemental information is carried out via the display of the COMAND operating, display and controller unit. On vehicles with code 810 Sound system, data exchange takes place between the COMAND controller unit and sound system amplifier over MOST. The audio output takes place over the following speakers:

IMPORTANT The audio signal for the bass box speaker travels from the COMAND operating, display and controller unit via MOST to the amplifier for sound system and from there, over direct lines via the subwoofer amplifier to the bass box speaker.

IMPORTANT In vehicles except code 810 Sound system, the audio output takes place using direct lines via the COMAND operating, display and controller unit and through the following speakers:

IMPORTANT The DVD/CD menu and title menu stored on the inserted DVD/CD appear on the display of the COMAND operating, display and controller unit. For this reason, the function scope and menu display are dependent on each respective medium. In the event that one of the two menus is missing on the DVD/CD, the display of the COMAND operating, display and controller unit provides the corresponding menu item with a gray background.

General Music Register, with code 527 COMAND APS with single DVD drive (with navigation) 

The integrated hard drive in the COMAND controller unit enables files (in MP3 format) to be stored from the CD over the SD interface and then called up as desired.

COMAND operating, display and controller unit, component description   GF82.85-P-3134TXB 
Sound system amplifier, component description With code 810 Sound system GF82.62-P-6003TM
Speaker system, component description Model 219 GF82.62-P-4220TXB
Model 211 GF82.62-P-4220TM
Subwoofer amplifier, component description With code 810 Sound system GF82.62-P-3050TM
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