There are several manufacturers out there that make flat cables, which presumably have lower impedance because the conductors are not so close together. I was thinking of making some from bulk computer ribbon cable (the kind that has been used to connect computer drives inside PCs for many years). They use silver coated copper conductors with Teflon dielectric. This is similar to some commercial audio cables that are very expensive. The bulk computer cable will require some careful dissection of the insulation at the ends since there are so many conductors, but it can be done. Anyone want to try them out when I complete them? They will probably be a pair of 8 foot speaker cables with banana plugs for the terminations.