No one actually knows how to lculate what speaker cable they need

It goes back to cable manufaturars, mostly provide no relevant data! to sales and the users. None will answer this!
Whay do you think that you own now the optimal cable to your setup?
I think I've figured it out. 

Honestly speaking, I have tried some different M1 settings in combination with the ribbons, but to my ears no major differences. I'm working out of town, so I can't check what the last settings are. All I can confirm that even IF there are differences, I can't distinguish them from each other with my ears, and using ribbons. In my case, other factors have a much bigger influence on the overall sound, and mainly with regards to room acoustics. Main reason for acquiring the M1 is related to dynamics and transparency. I can only judge by listening, I'm not an electrical engineer so I have to go with what my ears tell me. 
 Hi b4icu,
I cannot find the DF in the Goldmund Telos 600 manual. The cable length is 1.5 m. Thanks 
What gauge is your poweramps secondary windings? This size defines how much power your amp will be able to push out. Forget about the amps max wattt rating, it is the amps dynamic capasity that defines the need of wiregauge.

Mine has 2x9awg windings pr side so I`m running 7awg solid to the woofers
Mr.  khiak
Could you please provide me the serial numbers of your  Goldmund Telos 600 amplifiers?
Mr. Rodolphe from Goldmund Swiss asked me about it.
I'm waiting for his replay, but the S/N may help.
It is a mystery that this second Swiss firm, with extremely high end products, dosn't provide the data on their DFs.
Hi b4icu,
sorry for the late reply as I was not home. I have 5 Telos 600. 4 fo