2018 BMW 340i Speaker Sizes

The 2018 BMW 340i speaker size chart lists factory audio system specifications for replacement or aftermarket upgrade purposes. Information includes speaker locations throughout the vehicle: center dash, front door panel, rear deck lid, rear door panel, and below seats. Details provided assist in identifying compatible aftermarket speakers based on factory specifications.

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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 340i 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

Additional Notes

  • The 2018 BMW 340i factory audio system incorporates a multi-driver configuration with dedicated tweeters, midrange speakers, and a subwoofer positioned across multiple locations throughout the cabin.
  • Tweeters measuring 1 inch are installed in four separate locations: the center dash, front door panels, rear deck lid, and rear door panels, suggesting a focus on high-frequency dispersion throughout the listening environment.
  • Midrange drivers at 4 inches occupy the same four mounting locations as the tweeters, indicating a component-style setup rather than coaxial full-range speakers in most positions.
  • The subwoofer location below the seats may present space constraints for aftermarket upgrades, as under-seat installations typically limit the physical size and enclosure volume available for replacement units.
  • Replacing the 4-inch midrange drivers could potentially yield noticeable improvements in vocal clarity and instrumental detail, as this frequency range handles much of the core musical content.
  • The separate tweeter and midrange configuration allows for independent upgrades, meaning owners could replace one type without necessarily addressing the other, though matched component sets might provide better tonal balance.
  • The 1-inch tweeter size is relatively standard, which should provide reasonable compatibility with aftermarket component speaker sets designed for European vehicles.
  • The 8-inch subwoofer represents the sole dedicated low-frequency driver in the system, suggesting that bass reproduction relies entirely on this single under-seat unit.