Thanks again, all. It looks as if my choice is now (thankfully) just the Earmax Silver Edition or the WA2, unless someone tells me that either one or the other would be a mistake with the K701s. The WA2 might be the winner as it would be about £150 cheaper!
Again, tube rolling isn't really in the equation for me, not for now anyway. I'm amazed how fast I've been consumed by Head-Fi in just two short months, and tube rolling is a whole new world I want to stay away from. For now, anyway.
"In this pairing I discovered that the Anniversary wasn't all that stereotypically "tubey" sounding, probably the reason it didn't fare as well here with the K701. It barely added any real emphasis to the mid-range and instead rounded out some other edges of the sonic image - specifically treble, layering, and soundstage. Consistent across all headphones including the K701, the Anniversary didn't offer anything in the area of treble, and in fact downright detracted from it. Leading edges got dulled and lost bite, and there was no shimmer or sparkle. Violins never really sang on it and cymbal strikes always sounded incomplete too."