To be precise, you need the intersection between the pressure-vs-flow graphs of the filter and the fan. Finding those for fans is _somewhat_ doable if you're b

To be precise, you need the intersection between the pressure-vs-flow graphs of the filter and the fan. Finding those for fans is _somewhat_ doable if you're buying fans from a components store like Mouser, but that doesn't help that much if you don't also have at least some values for the filter. Actually, for fans, you'd ideally want a 3d graph of pressure-vs-flow-vs-noise.