Yes, indeed cable length . It’s not really about impedance but because where two dissimilar materials meet ( e.g. at the junction between cable and connector) the signal will be partially reflected. The cable needs to be of sufficient length to attenuate the back reflection and a “rule of thumb” minimum length is 1.5m. However there has been a fair amount of discussion here about the significance of this and you ( and the OP) may care to read this thread with its links. NB; The Apogee cables are the same as the Geistnotes, just a change of manufacturer:
I am not sure that I understand this question. Could you phrase it another way?