BMW 740i xDrive Rear Door Panel Speaker Size
The BMW 740i xDrive rear door panel accommodates a 1 inch speaker size and 4 inch speakers. Compatible types for these units include tweeter and midrange audio components within the system. These specifications cover the 2017 to 2018 replacement chart range.
| 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 door panel location in the BMW 740i xDrive accommodates 2 distinct speaker sizes simultaneously, indicating a multi-driver mounting configuration within the door panel structure.
- Door panel installations are typically surface-mounted or flush-mounted within dedicated cavities in the panel, with the door's internal frame and moisture barrier defining the available depth and diameter clearance.
- A 1-inch tweeter in the rear door panel occupies a small, shallow mounting footprint, consistent with the compact driver diameter required to reproduce high-frequency content accurately at short distances from the listening position.
- Tweeters handle upper frequency reproduction, generally spanning approximately 2,000 Hz to 20,000 Hz, and in a rear door panel position, the 1-inch driver contributes to high-frequency dispersion within the rear cabin seating area.
- The 4-inch midrange driver in the rear door panel requires a noticeably larger mounting cutout and greater cone excursion depth compared to the 1-inch tweeter sharing the same panel.
- Midrange drivers cover the vocal and instrumental frequency band, typically from around 300 Hz to 5,000 Hz, and a 4-inch unit in the rear door directs this frequency content toward rear seat occupants from a low, side-mounted angle.
- The combination of a 1-inch tweeter and a 4-inch midrange within the same rear door panel reflects a two-way speaker arrangement specific to that mounting zone, with each driver assigned to a separate portion of the audible frequency spectrum.
- The BMW 740i xDrive rear door panel accepts the same 1-inch tweeter and 4-inch midrange pairing across both the 2017 and 2018 model years, indicating dimensional consistency in the mounting locations between those years.
- Door panel speaker locations are subject to acoustic interference from window glass, door seals, and interior panel reflections, all of which interact differently with the high-frequency tweeter output versus the mid-frequency output of the 4-inch driver.
- A 4-inch midrange in a door cavity has limited low-frequency extension due to the shallow enclosure volume typically available within a door panel, reinforcing the driver's role as a mid-frequency rather than full-range unit.