2018 BMW M3 Speaker Sizes

The 2018 BMW M3 speaker size chart provides factory specifications for aftermarket replacement and audio system upgrade planning. Information covers speaker locations including center dash, front door panel, rear door panel, and below seats positions with corresponding factory sizes and mounting details for installation reference.

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Speaker Details by Location
Location Size Type Notes
Below Seats 8 Subwoofer
  • Very limited height clearance
  • Medium replacement priority
  • Replacement difficulty: medium
Center Dash 1 Tweeter
  • Requires dashboard disassembly
  • Medium replacement priority
  • Replacement difficulty: medium
Center Dash 4 Midrange
  • Requires dashboard disassembly
  • Medium replacement priority
  • Replacement difficulty: medium
Front Door Panel 1 Tweeter
  • Standard installation
  • High replacement priority
  • Replacement difficulty: low
Front Door Panel 4 Midrange
  • Standard installation
  • High replacement priority
  • Replacement difficulty: low
Rear Door Panel 1 Tweeter
  • Standard installation
  • Medium replacement priority
  • Replacement difficulty: low
Rear Door Panel 4 Midrange
  • Standard installation
  • Medium replacement priority
  • Replacement difficulty: low

2018 BMW M3 Speaker Replacement Summary

7 total positions
4 easy to replace
2 high priority
0 professional only

Replacement difficulty:

Low: 4 Medium: 3 High: 0

Replacement priority:

High: 2 Medium: 5 Low: 0

2018 BMW M3 Radio Slot Size (DIN)

DIN Type Size (inch) Size (mm) Notes
Double DIN 7"×4" 180×100 Double size for modern multimedia systems with large touchscreens
  • Always measure the slot before purchasing a new radio
  • Check slot depth - it may vary

Additional Notes

  • The 2018 BMW M3 audio system utilizes a three-way speaker configuration with dedicated tweeters, midrange drivers, and subwoofers distributed across multiple locations throughout the cabin.
  • Tweeter replacement may be considered a priority upgrade, as these 1-inch components handle high-frequency reproduction and significantly influence soundstage clarity and imaging precision.
  • The 4-inch midrange speakers installed in the center dash and door panels typically handle the critical vocal range, making their quality particularly important for perceived sound improvement.
  • Component speaker systems with separate tweeters and midrange drivers generally offer superior sound staging compared to coaxial designs, which this factory configuration already employs.
  • The under-seat 8-inch subwoofers provide low-frequency extension without consuming trunk space, though aftermarket replacements with higher power handling could enhance bass output.
  • Upgrading the midrange drivers before replacing tweeters might yield more noticeable sound improvement, as midrange frequencies carry most musical content and vocal information.
  • The double DIN radio opening allows for substantial aftermarket head unit options, which could provide additional power and signal processing capabilities for upgraded speakers.
  • Speaker sensitivity ratings and power handling specifications would determine whether amplification becomes necessary after installing aftermarket components in the existing locations.