BMW 335d Rear Door Panel Speaker Size
The BMW 335d rear door panel accommodates 1 inch speakers and a 4 inch speaker size across the model's production span. Compatible types for these locations include tweeter and midrange units. These specifications cover the 2009 to 2011 model years.
| Year | Type | Size (inch) |
|---|---|---|
| 2011 | Tweeter | 1 |
| 2011 | Midrange | 4 |
| 2010 | Tweeter | 1 |
| 2010 | Midrange | 4 |
| 2009 | 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 BMW 335d rear door panel accommodates 2 distinct speaker sizes across the listed model years: 1 inch and 4 inch.
- The rear door panel location positions speakers within an enclosed cavity, where the door's internal structure and surrounding trim affect both sound reflection and low-frequency resonance behavior.
- A 4-inch driver in a rear door panel operates in the midrange frequency band, typically covering approximately 300 Hz to 5 kHz, handling vocals, instruments, and the fundamental tonal content of audio reproduction at that location.
- Mounting a 4-inch midrange driver in a door panel places the cone relatively close to the listener's lower body, a position where direct midrange dispersion toward the listening area is limited by the angle and height of the mounting surface.
- The 4-inch cone diameter provides a moderate radiating surface, which supports adequate midrange output without the mass-related high-frequency rolloff that would affect a larger cone at similar frequencies.
- A 1-inch tweeter handles high-frequency content, generally from approximately 2 kHz to 20 kHz, reproducing transient detail, presence, and upper harmonic information that a midrange driver cannot efficiently reproduce at that range.
- The BMW 335d rear door panel places the 1-inch tweeter in close physical proximity to the 4-inch midrange, a pairing that allows the 2 drivers to share a crossover overlap region, typically in the 2 kHz to 5 kHz range, without significant spatial separation between sources.
- A 1-inch tweeter dome, the standard form factor for tweeters of that size, radiates high frequencies with relatively wide horizontal dispersion at lower treble frequencies and progressively narrower dispersion as frequency increases.
- Door panel mounting of a tweeter at door-panel height, rather than at ear or dashboard level, affects the vertical angle of high-frequency projection relative to seated occupants in rear seating positions.
- The 2009 model year lists only the 4-inch midrange and does not include the 1-inch tweeter, indicating a single-driver configuration at the rear door panel location for that year.
- The 2010 and 2011 model years share an identical rear door panel speaker configuration, with both the 1-inch tweeter and 4-inch midrange present at that location.