BMW 640i Rear Deck Lid Speaker Size
The BMW 640i rear deck lid accommodates a 1 inch speaker size and 4 inch speakers. Compatible types for these locations include tweeters and midrange units. These specifications cover the 2012 to 2018 model range.
| Year | Type | Size (inch) |
|---|---|---|
| 2018 | Tweeter | 1 |
| 2018 | Midrange | 4 |
| 2017 | Tweeter | 1 |
| 2017 | Midrange | 4 |
| 2016 | Tweeter | 1 |
| 2016 | Midrange | 4 |
| 2015 | Tweeter | 1 |
| 2015 | Midrange | 4 |
| 2014 | Tweeter | 1 |
| 2014 | Midrange | 4 |
| 2013 | Tweeter | 1 |
| 2013 | Midrange | 4 |
| 2012 | Tweeter | 1 |
| 2012 | 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 640i accommodates 2 distinct speaker sizes across all listed model years: 1 inch and 4 inch.
- The rear deck lid is a horizontal surface mounted at the rear of the cabin, behind the rear seating area, which positions speakers to radiate sound upward and forward into the passenger compartment.
- A 1-inch tweeter is designed to reproduce high-frequency content, generally spanning from approximately 2 kHz up to 20 kHz, where upper harmonics, transient detail, and high-frequency clarity are concentrated.
- The placement of a 1-inch tweeter in the rear deck lid directs high-frequency energy toward the headliner and rear cabin space, where treble frequencies contribute to the perception of spatial width and airiness in the rear soundstage.
- A 4-inch midrange driver handles the mid-frequency band, typically covering roughly 300 Hz to 5 kHz, which encompasses vocal presence, instrumental body, and much of the sonic content most audible to human hearing.
- At 4 inches, the cone diameter is small enough to maintain relatively controlled directivity across the midrange band, making rear deck placement acoustically practical for mid-frequency reproduction without severe beaming effects.
- The BMW 640i rear deck lid dual-size configuration pairs the 1-inch tweeter and 4-inch midrange within the same location, indicating a multi-driver arrangement within a single mounting zone on the deck lid surface.
- The rear deck lid mounting surface is typically a rigid, relatively flat panel, which can influence cabinet behavior for the drivers mounted within, as the surrounding structure partially substitutes for a dedicated enclosure.
- The 4-inch midrange driver, at a relatively compact diameter, requires a smaller mounting cutout than larger full-range or woofer drivers, which is consistent with the spatial constraints commonly associated with deck lid installations.
- Tweeters of the 1-inch diameter category are among the most common tweeter sizes, balancing high-frequency extension with adequate sensitivity, and the small footprint allows tight co-location with the 4-inch midrange within the deck lid panel.