I am using 2 Black Mambas (on transport and DAC) and three PS Audio Lab Cables plugged into a Hydra. I find the background to be much quieter than w/o the Hydra. Also tried the Hydra with the stock PCs and found a definite improvement with the high-end PCs in place. This is probably due to the fact that RF noise is being emitted/picked up by the stock PCs and not with the shielded PCs.
