2013 BMW 135i Speaker Sizes
The 2013 BMW 135i speaker size chart presents factory speaker specifications and locations for replacement or aftermarket audio system upgrades. Information includes specifications for speakers in the front door panel, rear deck lid, rear side panel, and below seats. Details cover factory speaker sizes and locations to assist with aftermarket audio system component installations.
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| Location | Size | Type | Notes |
|---|---|---|---|
| Below Seats | 8 | Subwoofer |
|
| Front Door Panel | 1 | Tweeter |
|
| Front Door Panel | 4 | Midrange |
|
| Rear Deck Lid | 1 | Tweeter |
|
| Rear Deck Lid | 4 | Midrange |
|
| Rear Side Panel | 1 | Tweeter |
|
| Rear Side Panel | 4 | Midrange |
|
2013 BMW 135i Speaker Replacement Summary
7
total positions
4
easy to replace
2
high priority
0
professional only
Replacement difficulty:
Low: 4 Medium: 3 High: 0Replacement priority:
High: 2 Medium: 3 Low: 22013 BMW 135i Radio Slot Size (DIN)
| DIN Type | Size (inch) | Size (mm) | Notes |
|---|---|---|---|
| Single DIN or Double DIN | 7"×2" or 7"×4" | 180×50 or 180×100 | Vehicle supports both radio sizes |
- Always measure the slot before purchasing a new radio
- Check slot depth - it may vary
Additional Notes
- The 2013 BMW 135i audio system incorporates a component speaker configuration with separate tweeters and midrange drivers rather than full-range coaxial speakers, which typically allows for more precise sound staging and frequency separation.
- Tweeters at 1 inch are distributed across three locations including front door panels, rear deck lid, and rear side panels, suggesting a multi-point high-frequency dispersion strategy throughout the cabin.
- The 4-inch midrange drivers mirror the tweeter placement pattern with installations in front door panels, rear deck lid, and rear side panel positions, indicating a dedicated mid-frequency reproduction system independent of low-frequency handling.
- An 8-inch subwoofer positioned below the seats provides bass frequencies, which represents a space-efficient under-seat mounting approach that preserves cargo area while still delivering low-end audio response.
- Replacing the factory tweeters could be prioritized when seeking improved high-frequency clarity or detail, as these smaller drivers handle the most directional and delicate portions of the audio spectrum.
- The midrange speakers at 4 inches handle vocal and instrumental fundamentals, making them candidates for upgrade when midrange warmth or presence lacks definition in the stock configuration.
- Component speaker systems like this configuration generally benefit from matching tweeters and midrange drivers from the same manufacturer or product line to maintain coherent crossover characteristics and tonal balance.
- The under-seat subwoofer location may present thermal considerations since this position typically receives less airflow than trunk-mounted alternatives, potentially affecting long-term voice coil temperatures during sustained high-output playback.
- Both single DIN and double DIN radio compatibility provides flexibility for head unit replacement, with double DIN allowing for larger touchscreen interfaces while single DIN maintains a more traditional dashboard aesthetic.