Franks, I am presently assessing the benefits of Hitachi FineMet beads on pigtails that you can use on your power cords. FineMet is much like ferrite beads but much more effective perhaps because of its bandwidth. For whatever reason, these give a dramatic improvement. I'm going to use them in an Exemplar modified Oppo 105. I am also seeing it a Monarchy regenerator driving a Nantais modified Lenco L78 and set to 110 volts, which was the US voltage at the time when Lenco was popular, sounds better. It clearly does.
In short, I am buried in tweak trials. There is magic to be found in music reproduction, but it is not easy to find it. Vibrations are the principle culprit.