Like a few have mentioned... A power cord is not going to solve your problems.
Here's part of what I think your problem is...Your preamp is not a good match for your amp. I believe Stereophile reviewed your preamp and the most useful part of those reviews are the measurements. Take a look and I think you'll find that your Pass amp does not have the optimal input impedance to mate with the Hovland.
Also, you may find that your JMlabs are not the right choice for your taste and room. The BE tweeter is an impressive piece of technology, but sometimes great individual parts don't make a great whole - just like combining a bunch of "recommended" components doesn't always make a great system.
Here's part of what I think your problem is...Your preamp is not a good match for your amp. I believe Stereophile reviewed your preamp and the most useful part of those reviews are the measurements. Take a look and I think you'll find that your Pass amp does not have the optimal input impedance to mate with the Hovland.
Also, you may find that your JMlabs are not the right choice for your taste and room. The BE tweeter is an impressive piece of technology, but sometimes great individual parts don't make a great whole - just like combining a bunch of "recommended" components doesn't always make a great system.