While Alembic pickups are, indeed, passive, they also have fewer windings than typical pickups. As a result they are low impedance, low output pickups. They require a preamp to boost their signal to typical guitar levels. So while the pickups themselves are passive, the Alembic “system” is active. And I believe there are some EMGs that have built-in preamps, but I could be wrong.
Bill, tgo