1988 BMW 735i Speaker Sizes

The speaker size chart for the 1988 BMW 735i provides factory audio system specifications and locations for replacement or aftermarket upgrade purposes. Information covers front kick panel and rear deck lid speaker positions. Details include specifications for each factory location within the audio system to facilitate aftermarket speaker installations.

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Speaker Details by Location
Location Size Type Notes
Front Kick Panel 4x6 Full-Range
  • Cramped working position
  • Medium replacement priority
  • Replacement difficulty: medium
Rear Deck Lid 5.25 Midbass / Full-Range
  • Access through trunk
  • Medium replacement priority
  • Replacement difficulty: low

1988 BMW 735i Speaker Replacement Summary

2 total positions
1 easy to replace
0 high priority
0 professional only

Replacement difficulty:

Low: 1 Medium: 1 High: 0

Replacement priority:

High: 0 Medium: 2 Low: 0

1988 BMW 735i Radio Slot Size (DIN)

DIN Type Size (inch) Size (mm) Notes
Single DIN 7"×2" 180×50 Standard size for basic car radios with small display or no display
  • Always measure the slot before purchasing a new radio
  • Check slot depth - it may vary

Additional Notes

  • The 1988 BMW 735i front kick panel speakers use a 4x6 inch rectangular format, which can accommodate full-range drivers that handle multiple frequency ranges through a single speaker element.
  • Rear deck lid positions accept 5.25 inch round speakers, offering flexibility between midbass drivers focused on lower frequencies or full-range speakers that cover broader frequency reproduction.
  • Upgrading the front kick panel locations may take priority for improving vocal clarity and midrange definition, as these positions typically direct sound toward the listening area more effectively than rear-mounted speakers.
  • The rectangular 4x6 inch form factor in front positions often presents tighter installation constraints than round speakers, potentially limiting aftermarket options to models specifically designed for this fitment.
  • Selecting midbass drivers for the rear deck could enhance lower frequency output when paired with separate tweeters or full-range front speakers, creating a component-style configuration.
  • Full-range speakers in both locations would provide a simpler replacement approach, maintaining the factory-style audio configuration without requiring additional crossovers or amplification.
  • The single DIN radio opening allows for aftermarket head unit installation, which could provide improved power output and signal processing to drive replacement speakers more effectively.