The Mitsubishi Van rear side panel accommodates a 6x9 inch speaker size in that location. Full-range units represent the compatible type available for audio installation. 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 Mitsubishi Van accommodates a 6x9 inch speaker opening.
A 6x9 inch speaker footprint requires a mounting surface with sufficient depth clearance behind the panel to house the driver basket without obstruction from structural framing or interior trim components.
The elongated oval geometry of a 6x9 inch driver produces a larger cone surface area than a circular 6.5 inch speaker, which increases low-frequency displacement capability within the rear side panel cavity.
Rear side panel positions are typically enclosed or semi-enclosed by interior trim, meaning the available airspace behind the mounting surface influences how a 6x9 inch driver handles bass frequencies.
The 6x9 inch format at a rear side panel location directs sound toward the passenger cabin from a lateral angle, contributing to rear-cabin fill rather than focused stereo imaging.
Full-range speakers are designed to reproduce the entire audible frequency spectrum-low bass, midrange, and high-frequency treble-from a single driver unit or a single driver combined with a passive crossover tweeter.
In a rear side panel position, a full-range driver handles all frequency content without requiring an external crossover network or a separate accompanying tweeter mounted elsewhere in the same zone.
The 1990 Mitsubishi Van rear side panel's compatibility with only the full-range type indicates the mounting location is sized and wired to support a single self-contained driver rather than a component speaker system requiring separate woofer and tweeter placements.