Audiotroy,You should email Coda to confirm, but the input impedance should be 10 kOhms for the balanced input and 50 kOhms for the unbalanced input.
what are the Coda 8 amplifier specs (input impedance?) cannot find them anywhere
Is there any difference as far as sound quality using balanced/unbalanced inputs?
Thanks,
Dan
As the amp has a fully differential input stage with a DC-coupled balanced input, that would be the purest signal path. Going through the AC-coupled unbalanced input would route the signal through additional circuitry. Whether this is audible likely depends on your ears and your particular room/equipment and whether you have any ground loops.
See: https://www.noiseengineering.us/blog/2017/5/12/ac-vs-dc-coupling-what-where-why ("Different types of voltage are handled differently at the input. DC-coupled inputs are the more straightforward: the circuitry just takes the input as it is. The entire signal passes through, more or less untouched. AC-coupled inputs are different. They include a capacitor in the circuit that allow them to filter out very low frequencies.")