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by Waterluvian 3123 days ago
I stack hard drives and they keep working.
1 comments

Absolutely. Hard disk drives don't stick to your refrigerator (like a naked magnet does) either. My layman's guess would be that the fields generated by the magnets in opposition in the voice coil are somehow "balanced", so that the net magnetic field produced by the drive is negligible.
It's simpler than that. They're held in an iron ring. This confines the field nicely, the permeability of the iron is quite high.