1981 Audi 4000 Speaker Sizes

The 1981 Audi 4000 factory audio system features a dashboard that accepts a 4 inch speaker size, while the front door panel and rear deck lid accommodate 5.25 inch units. Midrange, midbass, and full-range driver variants function as standard replacement and upgrade components for the vehicle acoustics.

Specific details regarding locations, speaker sizes, and types are outlined in the compatibility chart.

Speaker Details by Location
Location Size Type Notes
Dashboard 4 Midrange
  • Requires panel disassembly
  • Medium replacement priority
  • Replacement difficulty: medium
Front Door Panel 5.25 Midbass / Full-Range
  • Standard installation
  • High replacement priority
  • Replacement difficulty: low
Rear Deck Lid 5.25 Midbass / Full-Range
  • Access through trunk
  • Medium replacement priority
  • Replacement difficulty: low

1981 Audi 4000 Speaker Replacement Summary

3 total positions
2 easy to replace
1 high priority
0 professional only

Replacement difficulty:

Low: 2 Medium: 1 High: 0

Replacement priority:

High: 1 Medium: 2 Low: 0

1981 Audi 4000 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 1981 Audi 4000 features a three-location speaker configuration with size variations based on mounting position, suggesting a factory design that separated frequency ranges across different cabin areas.
  • Dashboard positions utilize 4 inch speakers designated for midrange frequencies, which typically handle vocal and instrumental content in the middle portion of the audio spectrum rather than full-range reproduction.
  • Both front door panels and rear deck lid accommodate 5.25 inch speakers with compatibility for either midbass or full-range types, providing flexibility in replacement strategy depending on whether a component or full-range system approach is preferred.
  • Midbass-capable speakers in the 5.25 inch locations would handle lower midrange and upper bass frequencies, complementing the dashboard midrange units in a multi-way configuration.
  • Full-range speakers in the door and deck positions would reproduce a broader frequency spectrum independently, potentially simplifying the system by reducing reliance on the smaller dashboard units.
  • The single DIN radio specification indicates a standard 2-inch tall head unit opening, which supports most aftermarket receivers without requiring dash modifications.
  • Replacement priority might focus on the front door 5.25 inch location first, as door-mounted speakers tend to provide more direct sound to occupants compared to dashboard or rear deck positions.
  • The size difference between dashboard and door/deck speakers suggests the original system likely directed higher frequencies forward through the smaller units while distributing midrange and bass content through the larger drivers.
  • Upgrading to quality full-range speakers in all three locations could provide noticeable improvements in clarity and tonal balance over aged factory units, particularly if original paper cone components have deteriorated.
  • Installing component midbass drivers in the 5.25 inch locations paired with separate tweeters would allow for more controlled frequency distribution and potentially higher fidelity than full-range alternatives.