#1 75R Digital Cable
Posted: Thu Apr 18, 2019 7:17 pm
After reading somewhere else, I am thinking of making up my own digital cable using a spare couple of meters of 4n silver run in PTFE sheathing that I have, a length of screen braid and using 'standard' RCAs.
One design I saw used an L-pad pair of resistors supposedly to match the cable impedance to the source and load 75R.
But isn't cable Zo=Sqrt (L/C), so is it folly thinking the performance can be optimised using a pair of resistors? But if I'm wrong, how do I determine the optimum values of the two resistors? I'm guessing I can get in the ballpark if I know or can measure the parameters of the cable I construct. And perhaps can be optimised with signal generator and scope.
Is the impact of a cable with different Zo going to noticeably affect performance of a lead from Squeezebox to Dac of less than 1m and guess max frequency of 96kHz?
Any advice would be appreciated.
One design I saw used an L-pad pair of resistors supposedly to match the cable impedance to the source and load 75R.
But isn't cable Zo=Sqrt (L/C), so is it folly thinking the performance can be optimised using a pair of resistors? But if I'm wrong, how do I determine the optimum values of the two resistors? I'm guessing I can get in the ballpark if I know or can measure the parameters of the cable I construct. And perhaps can be optimised with signal generator and scope.
Is the impact of a cable with different Zo going to noticeably affect performance of a lead from Squeezebox to Dac of less than 1m and guess max frequency of 96kHz?
Any advice would be appreciated.