BMW M240i xDrive Rear Side Panel Speaker Size
The BMW M240i xDrive rear side panel accommodates a 1 inch speaker size and 4 inch speakers. Compatible types for the location include tweeters and midrange units. These specifications cover the 2017 to 2018 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 side panel location in the BMW M240i xDrive accommodates 2 distinct speaker sizes, 1 inch and 4 inch, each assigned to a separate driver type.
- A 1-inch tweeter installed in the rear side panel handles high-frequency reproduction, typically operating in the range above 2,000 Hz, where short wavelengths require a small, lightweight diaphragm to maintain accurate transient response.
- The rear side panel placement of a 1-inch tweeter positions high-frequency dispersion toward the cabin's rear occupant space, where treble energy contributes to soundstage width and air in the upper registers of the audio image.
- A 4-inch midrange driver covers the vocal and instrumental frequency band, generally spanning roughly 300 Hz to 5,000 Hz, where cone diameter directly affects the driver's ability to move sufficient air for clear tonal reproduction without distortion.
- The 4-inch diameter is a compact midrange format, suited to door panel or side panel cavities with limited depth and surface area, where a larger driver would introduce fitment conflicts with the vehicle's interior structure.
- Mounting a midrange driver in the rear side panel positions mid-frequency output near the rear seating area, where direct radiation toward passengers reinforces vocal clarity and instrument body at close proximity.
- The BMW M240i xDrive rear side panel uses a two-way configuration at this location, pairing the 1-inch tweeter and 4-inch midrange to cover a broad frequency span across 2 physically separate drivers rather than a single full-range unit.
- The side panel mounting surface is typically flush or near-flush with the interior trim, which affects the baffle area available to each driver and influences the low-frequency extension a 4-inch midrange can achieve before rear-wave cancellation becomes a factor.
- Compatibility data for the BMW M240i xDrive rear side panel applies identically across the 2017 and 2018 model years, with 1-inch tweeters and 4-inch midrange drivers listed for both.