I went with a Hybrid. Silver Plated OCC Copper. One of the guys on the forum here made it for me. It could be my imagination but it seems like I don't need to cut the Treble on my HE400s any more... They DO seem smoother on the highs than with the stock 10 foot cable. Also seems like they get louder without distorting now too. I know, I know... It might just be wishful thinking, but I talked to the guy that made the cable and he said that's a common perception he hears from customers, so who knows? Here's a pic he sent me during fabrication.
I recognize those. The HeadRoom Micro amp was the giveaway :)