I have an early Master Control Center also. The early MCC came with the classic master coupler. I received it with a replacement power cord of an unknown source.
Though I have not tried the Synergistic Research power cords with it, I have tried different Brand Name power cords and couldn't tell the difference.
I could tell the difference between the active shielding being on or off with the ic's and speaker cables.
I could definately tell the difference with the Name Brand power cords replacing the stock power cords on my pre amp and cd player.
I'm not saying that there is not a difference, just that I couldn't tell the difference, the power cords all sounded the same to me.
Though I have not tried the Synergistic Research power cords with it, I have tried different Brand Name power cords and couldn't tell the difference.
I could tell the difference between the active shielding being on or off with the ic's and speaker cables.
I could definately tell the difference with the Name Brand power cords replacing the stock power cords on my pre amp and cd player.
I'm not saying that there is not a difference, just that I couldn't tell the difference, the power cords all sounded the same to me.