OK, not a full test but initial impressions after two hours of listening to assorted 16-bit commercial material and a live disc - panic, los lonely boys, and a 4060->DSD ambient recording.
Comparison was done between the Denon 2900 to PV14L
z-squared toplines on the mix-down ports
reality cables hanging off the LF,RF ports
PV-14 to premier 11a is z-squared toplines
This configuration lets me switch between two inputs on the preamp to compare cables. Much easier than the pre-amp to amp comparison for which I must power down the tubes.
Initially the two cables were indistinguishable. The sound stage was wide and deep for each. There was no obvious difference in frequency range - both seemed to be fairly wide range considering where the tubes top out. I still have a bass problem in my room, so not a great test environment in that respect.
After about an hour, the system was warm and the sound stage was at it's biggest and most airy. Now there was a difference to be heard but it was subtle. The two things I noticed were:
1) The z-squared cable had a deeper image. The reality cable image seemed to be a bit compressed from front to back. It wasn't a huge difference but the z-squared image seemed to go all the way to the back wall and the reality cable image seemed to stop about a foot or so shy of that and did not extend out as far in front of the plane of the speakers. The width of the image was about 18" each side of the speakers for both cables.
2) The reality cable had a different feel in the higher frequencies. I don't really know what to say here except that the cymbals seemed to have more presense and sounded maybe a bit more authentic. This wasn't brightness on the part of the reality cables (trust me I know brightness), it was just a subtle appealing characteristic of the reality cables.
So it was pretty much a wash. I want to swap ports just to see if my impression follows the cable. In the past, I tested the ports and they were identical, but the toplines have been attached for a while and maybe that makes a difference. There was also some very subtle difference in the instrument placement that I would not characterize as smear so I want to verify again that the perceived difference follows the cables and not the port.
Also, I'm going to try the reality cables in the preamp to amp path and I'll report on that.
Nick, do you have any problem with me treating the connectors on the reality cables? I have progold and silclear. The z-squared cables were treated with silclear some time ago. I was thinking of cleaning and treating both to see if that removed the differences. And on a side note, thanks again for the dyes. Amy wore hers (the long sleeve shirt) out today and she said that a lot of people turned to get a better look. Very nice ;-).