Why is the choke backwards in the Kaneda preamp?

[leadbelly]

Why does the Kaneda preamp have the common mode choke wired "backwards":

Why not as more commonly done:

[IMGDEAD]http://img223.imageshack.us/img223/2848/aaphonopsucorrected0js.jpg[/IMGDEAD]

 

[Eva]

The first schematic shows a differential-mode choke that filters ripple due to 50/60Hz rectification.

The second schematic shows a common-mode choke that filters EMI.

 

[leadbelly]

Thanks!