I suggest you ask Lamm for their recomendation(s). In general, I wonder why more people who post questions like yours don't do this. (Maybe they do, and post the question as well.) Not that the manufacturer's recommendation is to be taken as gospel. But it's information I'd like to have, whether I ended up paying much attention to it or not.
Best Lamm interconnects?
I have just ourchased a Lamm M1.1. I am interested in purchase the L1 preamp however I have been using balance interconnects with my current set up. Should I find another amp which would support balance interconnects or should I sell my balance cables and replace them with RCA??? Your advice would be greatly appreciated. Barry Smith