BMW 7 Series: HiFi Speaker System

The digital 7-channel HiFi amplifier is supplied by Lear. The HiFi system consists of a HiFi amplifier with the 12 speakers. This system is fitted as standard on the F01/F02.

Fig. 104: Identifying HiFi Speaker System Components

INDEX REFERENCE CHART

1. Tweeter, front right door
2. Mid-range speaker, front right door
3. Woofer, under right front seat
4. Tweeter, rear window shelf, right
5. Mid-range speaker, rear window shelf, right
6. Mid-range speaker, rear window shelf, left
7. HiFi amplifier
8. Tweeter, rear window shelf, left
9. Woofer, under left front seat
10. Mid-range speaker, front left door
11. Tweeter, front left door
12. Mid-range speaker, front center
13. Tweeter, front center

HiFi Amplifier

The HiFi amplifier is connected to the K-CAN for coding and diagnostics. The HiFi amplifier can be programmed but it is supplied by the manufacturer already preprogrammed at the factory.

The Audio signals are transmitted in analog form from the head unit to the HiFi amplifier. The internal digital equalizer adapts the audio signals specifically to the vehicle, as determined by the coding. The iDrive does not equalize any signals.

The adapted and amplified signals of HiFi quality are distributed through seven audio channels to a total of twelve speakers:

• One tweeter and one mid-range speaker in each of the front doors.
• One tweeter and mid-range speaker in the dashboard (center).
• One tweeter and one mid-range speaker on the rear shelf.
• One central bass speaker under each of the front seats.

The HiFi amplifier is located at the rear left of the luggage compartment behind the side panel trim.

Fig. 105: Identifying HiFi Amplifier With Safety Fuse And Connectors

INDEX REFERENCE CHART

1. Safety fuse
2. Connection for central bass speakers and power supply
3. Connection for audio signals, K-CAN and control signals

Top-HiFi Speaker System

The digital 10-channel Top-HiFi amplifier is also supplied by Lear. The 16 speaker Top-HiFi system is available as the premium option.

Fig. 106: Identifying Top-HiFi Speaker System Components

INDEX REFERENCE CHART

1. Tweeter, front right door
2. Mid-range speaker, front right door
3. Woofer, under right front seat
4. Tweeter, rear right door
5. Mid-range speaker, rear right door
6. Tweeter, rear window shelf, right
7. Mid-range speaker, rear window shelf, right
8. Mid-range speaker, rear window shelf, left
9. Top-HiFi amplifier
10. Tweeter, rear window shelf, left
11. Mid-range speaker, rear left door
12. Tweeter, rear left door
13. Woofer, under left front seat
14. Mid-range speaker, front left door
15. Tweeter, front left door
16. Mid-range speaker, front center
17. Tweeter, front center

Top-HiFi Amplifier

The features of the Top-HiFi amplifier are:

• MOST control unit
• Graphic 7-channel equalizer controlled by iDrive
• Playback of multichannel audio formats
• Higher output power in the low frequency range
• 15 V output voltage for each mid-range speaker/tweeter
• 30 V output voltage for each central bass speaker

The audio signals and the control signals are sent in digital form to the Top-HiFi amplifier through the fiberoptic cable (MOST).

Programming, coding and diagnostics are carried out via the MOST.

The Top-HiFi amplifier supports playback of multichannel signals in 5.1 format.

The signals are output in 7.2 format (seven mid-range/treble channels and two central bass channels).

Fig. 107: Identifying Top-HiFi Amplifier With Power Supply And MOST Connection

INDEX REFERENCE CHART

1. MOST connection
2. Reserved for load/logic separation, 10th channel preparation
3. Power supply, audio signals to speakers

Using those channels, the sound tracks on a DVD can be played directly and entirely independently on each individual channel. In combination, those sound tracks produce a surround sound effect. For that reason, the process is described as discrete multichannel playback.

There are normally two sound tracks recorded on a CD to reproduce the stereo signal, the usual practice on a DVD is to use the 5.1 format with 6 sound tracks.

To adapt that format best to the vehicle environment (two rows of seats), it is converted into 7.2 format and reproduced through seven mid-range/tweeter and two central bass channels.

For multichannel playback, the Top-HiFi amplifier decodes the digital data from the data source.

Multichannel audio formats can be played back both with the CIC player as well as the DVD changer.

The following multichannel audio formats are supported:

• Dolby Digital Surround
• Dolby Digital Surround Ex
• DTS (Digital Theater System)
• DTS-ES (Digital Theater System-Extended Surround)

The multichannel audio format is indicated on the DVD case.

The Top-HiFi amplifier supports Dolby Pro Logic II for calculating the spatial sound information from an existing stereo signal.

This process replaces Logic 7 known from other BMW vehicles. A surround sound effect can be computed from the stereo signal, which consists only of a left and right channel.

The signals of the individual channels are output with time correction from the 16 available speakers of the Top-HiFi system in the F01/F02. This produces a homogeneous sound effect for the listener in 7.2 format.

Audio playback can also be adjusted by the customer through the iDrive with the aid of the 7 channel equalizer integrated in the Top-HiFi amplifier.

After signals have been processed, the audio signals are forwarded as analog low frequency signals to the speakers.

The Top-HiFi amplifier supports speed-dependent equalization in addition to speed-dependent volume control.

The effect is that the frequency response is adjusted in relation to the speed of the vehicle.

A total of 16 speakers are controlled through nine amplifier channels with Top-HiFi quality:

• one tweeter and one mid-range speaker in each of the front doors.
• one tweeter and one mid-range speaker in the dashboard (center).
• one tweeter and one mid-range speaker on rear shelf.
• one central bass speaker under each of the front seats.

The Top-HiFi amplifier is located in the rear left of the luggage compartment behind the side panel trim. It is cooled by it's own cooling fan.

Fig. 108: Identifying Top-HiFi Amplifier With Additional Fan

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