Hey,
some gear newbie questions so I’m sorry but I have never before had to deal with these details. 
If I get myself a ISA ONE with digital output I will need a cable between the ISA and my MR816x. What type of cable? Does it matter which company’s cable quality wise?
And if I want a second preamp, the signal chain would be: 2nd preamp - ISA - MR816, right? Let’s say 'd choose the Blue Robbie. What type of cable do I need between the Blue Robbie and ISA?