How necessary it is will depend on the jitter reduction capabilities of the dac (if any), the risetime and falltime of the output signal from the upsampler or transport, the degree of impedance mismatch between cable, connectors, and interface circuits at both ends, and other factors. As Rcrerar suggested, the only way to tell for sure is to try it both ways.
BTW, it's not a matter of preventing signal reflections, it's a matter of affecting the timing of their propagation back and forth along the cable such that they don't arrive coincident with the critical parts of the original signal (the critical parts being their high-to-low or low-to high transitions).
Also, I would seriously question whether changing from copper to silver in the case of a short run of a digital signal will really accomplish anything.
Regards,
-- Al
BTW, it's not a matter of preventing signal reflections, it's a matter of affecting the timing of their propagation back and forth along the cable such that they don't arrive coincident with the critical parts of the original signal (the critical parts being their high-to-low or low-to high transitions).
Also, I would seriously question whether changing from copper to silver in the case of a short run of a digital signal will really accomplish anything.
Regards,
-- Al