So my bass came with a bunch of different strings on it. The E is a Spiro, the G is a Dominant, and the A and D, I'm not sure. Steve at Heinl's told me that they were made in Switzerland and are about $600 a set but didn't actually tell me the brand or anything. They are purple on the ends, and theres no ball, theres a sort of loop you have to put the string through after wrapping it through the bridge (kind of like a slip knot) and I'm pretty sure they're arco strings. Anyone know what these are? Thanks!