A funny story -- So in the above post I said I wanted to try the Nordost Qkore and experiment with the gain settings. So, I got home from work yesterday evening all excited. I plugged in the Qkore to the iTron grounding post and turned on the iTrons to get them warming up. I went to the gym while everything was settling in and warming up. When I returned home I sat down for a good listen expecting some greatness. What happened? Well, I fired up Beethoven piano concerto 1 and boom! WTF. The sound was dead and lifeless. I know it couldn't have sounded this bad when I left it the night before -- could it??. I tried a couple other pieces and dead, dead, dead. I was thinking how can this be. It is like the Qkore has a giant straw and is sucking the life out the music. So what else to do except unplug it and see what happens. Still dead sounding. Hmmmm. did something shift? So I go back to the beginning and start the process of understanding where it is wrong. So it happens that I switch to a song that I know is phase inverted so I click the button and then I immediately see the problem. The phase was inverted on Beethoven and the others when it wasn't supposed to be. Whew. set the phase correct and Listen again and all is now good. Back to the good baseline sound. So how did the changes go?
After the initial crisis, I now started with the gain adjustment. I listened a few times to the first major piano runs in Beethoven Piano Concerto 1. I then flipped the switch to turn the iTron gain down by 3dB and adjusted the L10 up by 3dB and listened again. As I expected the piano keys were much more crisp and dynamic. But the sound is a tad strident. Maybe too much gain. To me what this does is adjust the rise time (or leading edge) of each piano strike. This definitely cleared out some space between the notes.
I then went back and connected the Qkore to the iTron ground post and listened again. Wow, Wow, Wow! This cleaned things up a great deal. It seems that what the Qkore does is clean up the trailing edge -- more decay; more silence. Interestingly it also cleaned up the lower piano register a good bit. This makes some sense as the lower notes are "bigger" and really benefit from the extra space.
The sound is still a touch strident. I am positive a few more speaker adjustments are needed but there is still more to play with. I switched from Global to local feedback on the L10. This seemed to help a lot with the stridency and overall I think I like the sound of the local feedback setting better. I need to setup a shortcut key on the remote so I can switch back and forth more quickly to get a good grip on what all this does. I could also back off the preamp gain some and I am sure that will dial back the stridency. I also have not added any grounding boxes to any of the front end equipment yet.
The new settings exposed the fact that I needed to pull the speakers in toward the center just a touch -- about 1mm or less. After this and the requisite toe-in adjust and the timing is even better. Things are starting to get there. Slowly.