In 99% of cars, you adjust basic to most expensive "radios" so "sounds right" for the driver, everyone else is crap sound or worse "Screaming in One ear" even at lower volume for the Driver.
This is part of what 84 Fiero seat speakers was trying to fight. Give both seats some more left/right channels normally won't have.
Nearly all others adding big sound systems to any vehicle just want a "boom car" but claiming all kinds of BS to justify the cost.
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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)
The Ogre's Fiero Cave