also the maya 7.1 gold has that output.
although i can't find anywhere with that for sale either!

http://www.neoseeker.com/Articles/Hardware/Reviews/maya71/

I think there may be a few others but it's not a widely advertised connection, and seems unpopular now,

i'm keen to try this into a 568.2mm (when i get one!)

Main: 861v4, UHD722, 558, Klipschorn, SVS PC13u
second: Tom Evans Eikos, DCB1-pre, DIY Nelson Pass PLH amp, DIY speakers.