2018 BMW 320i Speaker Sizes

The speaker size chart for the 2018 BMW 320i provides factory specifications for replacement or aftermarket upgrade purposes. Information includes speaker locations throughout the audio system: center dash, front door panel, rear deck lid, rear door panel, and below seats. Details cover sizes and specifications needed when selecting aftermarket speakers to replace factory components.

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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 Deck Lid 1 Tweeter
  • Access through trunk
  • Medium replacement priority
  • Replacement difficulty: low
Rear Deck Lid 4 Midrange
  • Access through trunk
  • Medium 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 320i Speaker Replacement Summary

9 total positions
6 easy to replace
2 high priority
0 professional only

Replacement difficulty:

Low: 6 Medium: 3 High: 0

Replacement priority:

High: 2 Medium: 7 Low: 0

2018 BMW 320i 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 320i uses a uniform 1-inch tweeter configuration across all cabin positions, with identical units installed in the center dash, front door panels, rear deck lid, and rear door panels.
  • A matching set of 4-inch midrange speakers mirrors the tweeter placement pattern, occupying the same four locations throughout the cabin for consistent frequency coverage.
  • The audio system incorporates an 8-inch subwoofer positioned below the seats, serving as the dedicated low-frequency component in what could be characterized as a three-way speaker arrangement.
  • Upgrading the midrange speakers may yield noticeable improvements in vocal clarity and instrumental definition, as these 4-inch units handle the critical frequency range where most musical content resides.
  • The tweeter locations suggest a design approach focused on dispersing high frequencies from multiple points, potentially creating a wider soundstage than single-location tweeter installations.
  • Subwoofer replacement or enhancement might be prioritized for listeners seeking stronger bass response, though the under-seat location may present spatial constraints for larger aftermarket units.
  • The double DIN radio opening provides sufficient space for aftermarket head units with advanced features, including those with built-in amplifiers or enhanced digital signal processing capabilities.
  • Component speaker systems designed for three-way configurations could integrate well with this factory layout, as the existing tweeter and midrange separation aligns with typical aftermarket component architecture.
  • The rear deck lid speaker placement indicates sound projection toward the cabin rather than into the trunk area, contributing to rear passenger audio quality.
  • Matching impedance and power handling specifications becomes particularly relevant when replacing speakers across multiple locations, as mismatched units could create tonal imbalances between front and rear soundstages.