2008 Yaris sedan ‘S’ sound deadening project.

[talnlnky]

those aren't usually called electronic crossovers. They are normally just called passive crossovers because they don't require a power source to operate. If you call them electronic crossovers, people might think you are talking about active crossovers which are the crossovers built into your amplifier, or a stand alone powered crossover like this

Also, passives 99.9% of the time are installed in line with the speaker wire, where as active is installed in line with the signal cable(RCA's). that .1% of the time I alluded to are things called Fmods

Hope you have a free weekend, cause you have your work cut out.