The Nissan Sentra rear side panel accommodates a 6x9 inch speaker size. Full-range units represent the compatible type for the audio system. These specifications cover the 1990 model year.
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 side panel location in the 1990 Nissan Sentra accommodates a 6x9 inch speaker opening, an elongated oval format that fits within the contoured interior panel structure of the rear cabin area.
A 6x9 inch speaker footprint requires a mounting depth and panel cutout sized to the oval dimensions, meaning the rear side panel must provide adequate clearance behind the mounting surface to house the driver basket without obstruction.
The 6x9 inch format produces a larger cone surface area than circular mid-size speakers, which translates to greater air displacement capacity within the rear side panel enclosure space.
Mounted at the rear side panel position, a 6x9 inch speaker operates within a location that is angled toward the cabin interior, influencing the directional projection of sound toward front and rear seat passengers.
Full-range is the sole compatible speaker type listed for the 1990 Nissan Sentra rear side panel, designating a single driver unit engineered to reproduce the audible frequency spectrum from low bass through high treble without a supplemental crossover-divided driver.
A full-range driver in the 6x9 inch format typically integrates a woofer cone with an attached whizzer cone or internal tweeter, allowing the single unit to handle both low-frequency and high-frequency reproduction from 1 mounting point.
In a rear side panel position, a full-range speaker handles the complete audio signal independently, meaning no additional component speakers or crossover networks are required to support frequency coverage at that location.
The rear side panel placement positions the speaker closer to the rear seat occupants than to the front, affecting the spatial balance and proximity of audio output relative to different seating positions in the cabin.