Yes, that’s how you do it - Just ensure only the telephone fader has the “talkover” button active to that it is removed from the Tape Out on the top of the desk. Also ensure that the Talkover settings are either low or completely off otherwise every little blip from the telephone line will make the other channels “duck”.
Ah I see. Usualy I use the talkover-function on my mic to talk over the background music. So if I disable this at my mics channel and enable it on the telephones channel, I get a N-1 output. Thanks for that great hint!
Best regards
Dominique Görsch