I'd appreciate an explanation I can understand as to why Power cords & digital cables make a dramatic difference with transports, but not with an hd.I attempted to explain that, with respect to digital cables, in my post in this thread dated 8-4-13.
Basically, differences in digital cables connecting transports and DACs can directly affect the signal that is received by the DAC in such a way as to affect jitter (timing fluctuations) when the digital signal is converted to analog within the DAC. Jitter at the point of digital to analog conversion has directly audible effects. A lot has been written on that subject.
None of that has any relevance to the connection between between a USB hard drive and your Oppo.
As far as power cords are concerned, if I recall correctly you are using a bus powered drive that does not have an AC power cord or power supply. So the drive receives 5 volt DC power from the Oppo, while a transport receives 120 volt AC power. A transport is a physically large component containing extensive amounts of circuitry and parts that generate electrical noise, which can be fed back into its power cord and pollute the AC that is received by other components. Again, none of that has any relevance to the situation of a bus powered USB hard drive.
Now, I am not saying that it is impossible for the cable connecting your hard drive to the Oppo to have any audible effects. But if it were to, it would be in ways that are subtle, indirect, unpredictable, and much less audibly significant than in the transport to DAC situation. What I am basically saying is that the fact that you have found cables to make major differences in the transport situation should not create an EXPECTATION that differences will occur in the hard drive situation.
Regards,
-- Al