Do you want to control all of them separately or all of them at the same time?
Typically, I would recommend Aqua Computers Quadro and Octo, but due to teething issues with updating the firmware (and hence the software too since they're linked) on their Octo series, I would only recommend their Quadro series right now.
But the Quadro only has 4 channels for control of fans, so if you want to control all 9 of those fans individually, this likely won't do. If you control them in banks (front intake, top exhaust, etc) then the Aqua Quadro could be something you might want to look into. And the Octo wouldn't be able to control all 9 individually either unless you pair at least two of them together onto one channel. And its teething issues probably aren't worth the hassle in getting them resolved.
So, my recommendation (if you are controlling the fans in banks), the Aqua Computer Quadro PWM controller.