Sound differences between Copper and Aluminum Bus Bar Electrical Panels

I have a Square D Homeline electrical panel that has an aluminum bus bar and I'm wondering if anyone hear went through the trouble to change the electrical panel to a copper bus bar type such as the Square D QO or any other manufacturer.  What audio improvements were heard going from aluminum to copper????  My system consists of top end components with a full loom of SR Galileo UEF cables, SR Active Grounding Block SE and an SR Powercell 12 UEF ac power conditioner.