Can anybody please help me identify a plug socket


I’ve recently acquired an Acorn Audio Comparator which is an old box that allows you to route between audio sources, amos and speakers in any configuration. The problem is that I can’t identify the input sockets on the back and can’t find the corresponding connector.

I think the mains socket is a Bulgin 3 pin but it’s the round metal sleeved sockets I’d like to know about. If anyone can help I’d be very grateful.

https://photos.app.goo.gl/cNPPBJmNJCK8YSPe6

Many thanks

John

shed_dweller
Thanks for your help guys. The only 2 pin din I could find has a large flat pin and s small thinner one. 
The cannon plugs look a bit closer to mine but the sockets I have are not threaded. I found a 2pin xlr type cannon plug which look very close. Could it be an for type socket, only there isn't a catch on it, only the thin channel in the sleeve. 

Any other ideas?
Looks proprietary. Good luck with that.
I don't think I'd trust it even with the oem plugs.