I also have a Studer 900 series console dating from 1982
This console was originally installed in a broadcast van, and above the orange phones there is a control panel to ajust the van's heating system!
I bought this desk on ebay about 1.5 years ago, and travelled to the middle of germany in a van to pick it up. The seller had the best moustache i have ever seen
The 900 series was their most popular console and it sounds absolutely stunning, with a kind of edgy 80s sound, very different from the 70s MCI 416b. In the next picture you can see how my room is currently set up, with the 2 analog desks along side a Mackie DXB, which is useful for certain things [recall mainly] but sounds like a toy next to the real things