Thanks Al. I think that you are completely right about the system dependence. I'm using a Lightspeed LDR clone preamp and it's definitely sensitive to impedance match in both input and output directions in terms of components, so it's not surprising that the same is true of cables.
Hero vs Goertz did a comparison
Never done a cable head to head before until now but I had wanted to try the Goertz MicroPurl Copper interconnects for a while. My new preamp seemed to lack some sparkle on the top end, and I thought maybe is was a cable match situation. I was right. The Goertz has definitely brought back the highs that were sounding a bit rolled off with the Hero with the new preamp. I went back and forth a couple of times and the Goertz was a clear winner on all three LPs that I tested. The cables are airy-er and have a better, deeper soundstage. I'm now of course wondering if I should try the Goertz silver.