Dating an Orange 12 Channel mixing desk

[JC]

Hi !

I'd like to know the age of my 12 Channel mixing desk, build by Orange in the late 70's.
On the rear panel is written:

" ORANGE music
3/4 new Compton St.
London W.C.2
SER.NO.L.S. 8548 "

Do you know when Orange was at this adress in London ?

Thanks in advance for your answers.

Best regards,

JC


ABBA forever !