There may be another factor, and that has to do with the use of the 840c.
I have another post where I describe the use of the 840c as a player into a Bryston BDA-1. I found a similar reduction in clarity when using the upsampled digital outputs of the 840c into the Bryston. Only the raw 16/44.1 data from the player sounded as good or better than the CD player (840c) alone.
My point is that if you are comparing a digital input to the 840c vs a CD being played by the 840c, I suspect there may be a quality loss entering the digital process stream of the 840c. This is irrespective of cables.
This may be due to the 840c design where the system is optimized very well to take it's player output and upsample it to the DAC. If you interrupt this stream going either direction, audio quality suffers, even though its in the digital process streams where (theoretically) it should not make a difference.
I have another post where I describe the use of the 840c as a player into a Bryston BDA-1. I found a similar reduction in clarity when using the upsampled digital outputs of the 840c into the Bryston. Only the raw 16/44.1 data from the player sounded as good or better than the CD player (840c) alone.
My point is that if you are comparing a digital input to the 840c vs a CD being played by the 840c, I suspect there may be a quality loss entering the digital process stream of the 840c. This is irrespective of cables.
This may be due to the 840c design where the system is optimized very well to take it's player output and upsample it to the DAC. If you interrupt this stream going either direction, audio quality suffers, even though its in the digital process streams where (theoretically) it should not make a difference.