1978 BMW 733i Speaker Sizes
The 1978 BMW 733i speaker size chart provides specifications for factory and aftermarket audio system components. Information includes speaker locations in the front kick panel and rear deck lid areas. Details cover replacement and upgrade options, helping to identify compatible audio specifications for the factory system or aftermarket installations.
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| Location | Size | Type | Notes |
|---|---|---|---|
| Front Kick Panel | 4x6 | Full-Range |
|
| Rear Deck Lid | 5.25 | Midbass / Full-Range |
|
1978 BMW 733i Speaker Replacement Summary
2
total positions
1
easy to replace
0
high priority
0
professional only
Replacement difficulty:
Low: 1 Medium: 1 High: 0Replacement priority:
High: 0 Medium: 2 Low: 01978 BMW 733i Radio Slot Size (DIN)
| DIN Type | Size (inch) | Size (mm) | Notes |
|---|---|---|---|
| Single DIN | 7"×2" | 180×50 | Standard size for basic car radios with small display or no display |
- Always measure the slot before purchasing a new radio
- Check slot depth - it may vary
Additional Notes
- The front kick panel speakers in the 1978 BMW 733i typically warrant replacement consideration first, as these 4x6 inch full-range units handle most of the audible frequency spectrum from a position that directly projects sound toward occupants.
- Full-range speakers at the front kick panel locations reproduce both mid and higher frequencies without requiring separate tweeters or crossover networks, which tends to simplify installation while maintaining audio clarity.
- The rear deck lid accommodates 5.25 inch speakers that can function as either midbass drivers or full-range units, allowing for flexibility in system configuration based on whether front speakers already handle higher frequencies adequately.
- Midbass speakers in the rear deck position would focus on reproducing lower midrange and upper bass frequencies, potentially filling out the sound stage when paired with full-range front speakers.
- Upgrading to contemporary speaker technology in both locations may enhance clarity and frequency response compared to original equipment, particularly in the upper frequency ranges where older designs often showed limitations.
- The single DIN radio opening suggests head unit replacement could complement speaker upgrades by providing improved amplification and signal processing capabilities.
- The 4x6 inch front speaker size represents a non-circular configuration that was common in this era, which may require adapters or custom mounting solutions when installing modern speakers designed primarily in round formats.
- Rear deck speakers positioned at 5.25 inches offer reasonable cone area for mid-bass reproduction while fitting within the space constraints of the deck lid structure.