BMW M240i xDrive Rear Deck Lid Speaker Size
The BMW M240i xDrive rear deck lid accommodates 1 inch speaker size units and supports 4 inch speakers. Compatible types for the location include tweeters and midrange audio components within the system. These specifications cover the 2017 to 2018 range of model years.
| Year | Type | Size (inch) |
|---|---|---|
| 2018 | Tweeter | 1 |
| 2018 | Midrange | 4 |
| 2017 | Tweeter | 1 |
| 2017 | Midrange | 4 |
Speaker Types
| Type | Description |
|---|---|
| Tweeter | A small driver built for high frequencies, typically from about 2,000 Hz to 20,000 Hz. It adds treble detail and clarity and is usually mounted near ear level or aimed at the listener. |
| Midrange | A driver for the middle of the audible range, typically from about 300 Hz to 5,000 Hz, where vocals and most instruments sit. It is often paired with a tweeter and a woofer. |
Additional Notes
- The rear deck lid of the BMW M240i xDrive accommodates 2 distinct speaker sizes, 1 inch and 4 inch, each assigned to a different acoustic role within the same installation zone.
- A 1-inch tweeter in the rear deck lid position handles high-frequency reproduction, typically operating in the range above 2,000 Hz, where short wavelengths benefit from the elevated and rearward-facing surface that a deck lid provides.
- The 4-inch midrange driver in the rear deck lid covers the middle portion of the audible frequency spectrum, generally spanning from around 300 Hz to 5,000 Hz, a range that includes vocal fundamentals and upper harmonics.
- A 4-inch cone diameter in a midrange driver produces a relatively focused dispersion pattern, which is consistent with placement in a rear deck lid where the driver radiates toward the cabin ceiling and rear passenger area.
- The rear deck lid is a horizontal surface, meaning both the 1-inch tweeter and 4-inch midrange driver are oriented to project sound upward and forward into the passenger cabin rather than directly at ear level.
- The BMW M240i xDrive rear deck lid supports a 2-way speaker arrangement at this location, pairing a tweeter and a midrange driver to divide frequency reproduction between 2 distinct transducer types.
- A 1-inch tweeter relies on a small diaphragm to reproduce high frequencies with accuracy; in a rear deck lid location, the proximity to the rear windshield can introduce reflective surfaces that interact with high-frequency output.
- The 4-inch midrange specification at the rear deck lid indicates a physically constrained mounting cavity, as the deck lid's panel depth and structural bracing typically limit available enclosure volume for larger cone drivers.
- Both speaker sizes listed for the BMW M240i xDrive rear deck lid remain consistent across the 2017 and 2018 model years, indicating no dimensional or type changes were introduced between those 2 years for this location.