https://image.ibb.co/gQhXXp/mini_edit.jpg
Maybe later I will cut a big whole in the backplate.
https://preview.ibb.co/my7hXp/IMG_20180828_190527_HHT.jpg
Stats of the dualfan Z9 mini
https://image.ibb.co/cF1ZCp/mini1.jpg
Stats of the normal Z9 mini
https://image.ibb.co/jEPXyU/mini_2.jpg
EDIT
Some thoughts, the big advantage is that the miner have now enough power to push the Air out. My problem is that there is no good way to install the hose. Does anybody know where to get a backplate with screws for the other side.
The hose (I'm not sure about the right word in english)
https://preview.ibb.co/kNWFk9/IMG_20180828_200519_HHT.jpg
I couldn't get a hold of the backplate either, I asked around local mechanical workshops, all quoted me $200++ for making such plate in aluminium.
If you know someone with access to a CNC then maybe you can get it done for a reasonable price.
In my case, I 3D modelled a fan mounting bracket( aka cowl) and got it printed locally ( 3dhubs.com), it costed about $15.
The cowl is attached to the backside of the antminer with duct-tape.
The hose you are referring to is called a duct, sonodec on the other hand is a hose.
The duct is attached to the fan, and the fan to the cowl. M4 screws, nuts and washers can be obtained locally.
So my setup goes like this:
flexible hose -> duct -> exhaust fan -> cowl -> Z9 mini -> intake fan
I can upload some pictures later once I get home.