Audi 100 Series Rear Deck Lid Speaker Size
The Audi 100 Series rear deck lid accommodates a 5.25 inch speaker size across all listed model years. Compatible types for the location include midbass and full-range audio system units. The specifications cover a range of 1970 to 1973.
| Year | Type | Size (inch) |
|---|---|---|
| 1973 | Midbass / Full-Range | 5.25 |
| 1972 | Midbass / Full-Range | 5.25 |
| 1971 | Midbass / Full-Range | 5.25 |
| 1970 | Midbass / Full-Range | 5.25 |
Speaker Types
| Type | Description |
|---|---|
| Midbass | A driver tuned for upper bass and lower midrange, roughly from 80 Hz to 500 Hz. It has longer cone travel than a full-range unit, which supports stronger bass in doors and panels. |
| Full-Range | A single driver that reproduces bass through treble without a separate crossover network. It is the simplest replacement option and is common in factory audio systems. |
Additional Notes
- The rear deck lid is a horizontal surface positioned at the rearmost section of the passenger cabin, typically spanning the width of the vehicle beneath the rear window. Speakers mounted in the deck lid fire upward toward the rear glass, which acts as a reflective boundary that disperses sound forward into the cabin.
- The mounting depth available in a rear deck lid is generally shallow relative to door locations, as the panel must accommodate the trunk seal, structural bracing, and body sheet metal beneath the surface.
- A 5.25-inch driver occupies a mid-sized cone diameter, producing a balance between low-frequency extension and upper midrange clarity that suits a rear deck position where bass reinforcement and vocal reproduction both contribute to cabin fill.
- At 5.25 inches, the cone area is sufficient to move enough air for midbass output without requiring the deeper enclosure volume that larger woofer diameters demand, making the format compatible with the limited depth of a deck lid panel.
- The midbass type is a driver optimized for the frequency band roughly between 80 Hz and 500 Hz, covering the lower midrange and upper bass registers where kick drum, bass guitar fundamentals, and male vocal weight are concentrated.
- In a rear deck lid position, a midbass driver at 5.25 inches reinforces low-frequency energy that tends to diminish toward the front of the cabin, compensating for the distance between the listening position and front-mounted audio sources.
- The full-range type is a driver designed to reproduce frequencies across a wide spectrum, typically from the upper bass through the high treble, allowing a single driver to handle the entire audible range without a dedicated crossover network.
- A full-range driver in the Audi 100 Series rear deck lid position reproduces midrange and treble detail that projects forward along the cabin ceiling plane, contributing ambient and spatial content to the overall sound field.
- The 5.25-inch full-range format in a rear deck application produces directionality that is broad at lower frequencies and increasingly narrow at higher frequencies, with the rear glass helping to diffuse high-frequency output before it reaches the front occupants.
- The Audi 100 Series rear deck lid across the 1970 through 1973 model years accepts a 5.25-inch driver, indicating a consistent cutout diameter and mounting bolt pattern held across the full production span represented in the specifications.