2011 BMW 135i Speaker Sizes
The 2011 BMW 135i factory audio system contains specific speaker locations. Front door panel, rear deck lid, and rear side panel locations accommodate 1 inch speakers and 4 inch units, while below seats locations accept an 8 inch speaker size. Compatible speaker types for replacement and upgrade include tweeter, midrange, and subwoofer units.
Specific details regarding locations, speaker sizes, and types are outlined in the compatibility chart.
| 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 |
|
2011 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: 22011 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 2011 BMW 135i utilizes a component speaker configuration with separate tweeters and midrange drivers rather than full-range coaxial speakers.
- Tweeters are positioned in three locations throughout the cabin, with 1 inch units found in the front door panels, rear deck lid, and rear side panels.
- Midrange drivers complement the tweeters across the same three locations, with 4 inch units installed in the front door panels, rear deck lid, and rear side panels.
- An 8 inch subwoofer positioned below the seats handles low-frequency reproduction in the factory audio configuration.
- Upgrading the midrange speakers may provide more noticeable sonic improvements than tweeter replacement, given their larger surface area and broader frequency range responsibilities.
- Component speaker systems typically offer better soundstage and imaging compared to coaxial designs due to the physical separation of high and mid-frequency drivers.
- Aftermarket speakers matching these sizes would need to accommodate the vehicle's existing mounting points and electrical connections.
- The factory subwoofer location below the seats suggests a space-efficient design that preserves trunk and passenger area while still providing bass extension.
- The radio accepts both single DIN and double DIN head unit replacements, offering flexibility for audio system upgrades.