Bose Mercedes W140 / C140 Sound System

Tech
Audio, Auto

There are two generations of the amplifier in the Bose Mercedes W140 S-Class and C140 CL-Class Coupe.

First generation Bose Mercedes W140 Amplifier

The 1st generation of the W140 amplifier, found in the 1992-1993 S-Class, has 6-channels output and is placed in the trunk, under rear deck, above the wheel. Total power output is advertised at 275W. There are 7 amplifier modules inside, three of these amplifier boards being powered by the TDA7256 chip.

The TDA7256 is a class AB fully protected bridge power amplifier, designed for car radio applications. The high current capability allows to drive low impedance loads (up to 2 Ohm). The differential inputs availability makes it particularly suitable for boosters and active loudspeakers applications.

Channel outputs are as follows:

  • Front Speakers – full range
  • Rear Door speakers – high pass
  • Rear Deck speakers – low pass
  • Mirror mounted speaker – high pass

Second generation Bose Mercedes W140 amplifier

The 2nd generation amplifier, found between 1994-1999, is smaller and is located in the left side of the trunk, right above wheel well.

Bose Mercedes W140 / C140 / V140 Speakers

W140 is the short S-Class, V140 is the long version and C140 is the CL Coupe.

There are a total of 11 speakers on the Mercedes-Benz W140 S-Class:

  • 2 Front doors, 11.4 cm low-mid-range speakers, in a ported enclosure
  • 2 Front doors, 7.6 cm tweeter
  • 2 Rear doors, 9 cm wide-range speakers
  • 4 Rear shelf, 16.5 cm woofers, using trunk as an infinite baffle

The Mercedes-Benz part numbers:

  • 140 820 11 89 (C140) – Amplifier
  • 140 820 18 02  – 4 x Woofers(C140) – (dark gray cones)
  • 140 820 05 02 + 140 820 06 02 – Front Doors L+R  (same on W140 / C140 / V140)
    • Enclosures with 1 low-range and 1 mid-range speakers each
  • 140 820 19 02 + 140 820 20 02 – Rear Doors L+R
  • Center 140 820 12 02

C140 variations

  • 140 820 11 89 – Amplifier
  • 140 820 19 02 + 140 820 20 02 – Rear Left+Right side panel
  • 140 820 18 02 – 4x woofers

W140

  • 140 820 ?? 89- Amplifier
  • 140 820 02 02 – 4x woofers (reddish cones)
  • 140 820 08 02 + 140 820?07?02
    Enclosure, long and thin with 1 speaker each