1990 Infiniti M30 Speaker Sizes
The 1990 Infiniti M30 factory audio system features front door panels that accommodate a 4 inch speaker size, alongside a rear deck lid that accepts 6x9 inch units. Midrange and full-range driver units serve as compatible speaker types during a replacement or upgrade procedure.
Specific details regarding locations, speaker sizes, and types are outlined in the compatibility chart.
| Location | Size | Type | Notes |
|---|---|---|---|
| Front Door Panel | 4 | Midrange |
|
| Rear Deck Lid | 6x9 | Full-Range |
|
1990 Infiniti M30 Speaker Replacement Summary
2
total positions
2
easy to replace
1
high priority
0
professional only
Replacement difficulty:
Low: 2 Medium: 0 High: 0Replacement priority:
High: 1 Medium: 1 Low: 01990 Infiniti M30 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 1990 Infiniti M30 contains two distinct speaker locations with different size requirements, suggesting a basic two-way factory audio configuration where front speakers handle mid-frequency content while rear speakers manage broader frequency ranges.
- Front door panel speakers use 4 inch midrange drivers, which typically focus on vocal frequencies and instrumental detail between approximately 200Hz and 5000Hz rather than attempting to reproduce the full audible spectrum.
- The rear deck lid accommodates 6x9 inch full-range speakers, a common oval format in vehicles from this era that allows for greater cone surface area within limited mounting depth constraints.
- Full-range speakers in the rear position would handle bass, midrange, and treble frequencies simultaneously through a single driver design, contrasting with the dedicated midrange function of the front speakers.
- Replacement of the rear deck speakers might produce more noticeable sound quality changes than front speaker upgrades, given their full-range responsibility and larger cone area for bass response.
- The radio supports both single DIN and double DIN aftermarket head units, providing flexibility for audio source upgrades that could better drive replacement speakers with higher power handling capabilities.
- Aftermarket 4 inch midrange speakers often feature better voice coil materials and suspension components than factory equivalents, potentially improving clarity in the critical vocal frequency range.
- Modern 6x9 inch full-range speakers typically incorporate separate tweeters within the same frame, offering improved high-frequency extension compared to single-cone designs common in factory installations.
- The combination of different speaker types suggests the factory system relied on natural acoustic rolloff characteristics rather than electronic crossover filtering to divide frequency responsibilities.