I have no idea what power cord fits this equation.
I'm just posting so I can check back easily later on what others might recommend. also the Wired 4 Sound is a device I have interest in.
When you say that these instruments come across "aggressively", what does that mean exactly? Are things just too hot on the top end? Is there graininess or sibilence or other kinds of audible distortions?
How do you know that a different power cord is the solution? Sounds like you have the system pretty doctored up already in regards to electrical power. have you tried stripping out all or some combo of the tweaks to see what that does?
Do you have another source besides the Consonance to compare that might sound different?
Off the cuff, I'm suspicious of the CD direct into Wyred combo. A different tube or two in this path, via DAC and/or pre-amp or alternate tubes in the Consonance, if possible, might help, but that is just a gut feel on my part.