+1 about cables (interconnects) making a difference.
using some short 30~75cm line-level interconnects between Bifrost Multibit (gen 1), Lokius, Asgard 3, I can hear differences between old (1990's) xlo Pro100, and recently built Belden 1505F, and Mogami 2549. In my test config, all three cables sound different, the Pro100 (130pf) sounds the brightest, less bassy, and with more low-level detail present than the other two. the Belden 1505F (~20pf) and Mogami 2549 (~30pf) cables have similar low capacitance, but sound uniquely different from each other, so there's more here than typical R / L / C steady-state parameters involved. The Pro100 uses a litz wire and gold-plated RCA's, making oxidation of the conductors an unlikely factor in the audible differences.
I believe there are non-linear time-domain characteristics involved and not yet quantified or typically measured that would correlate with observed sound qualities. A recent (1~2 wks ago IIRC) post pointed out that the signal propagation velocity (aka VP, typically specified as a percentage relative to the speed of light) is not only a function of the conductor material (e.g. copper, silver, alloy), but the dielectric (e.g. air, teflon, PE, PVC) as well.
The 'directionality' of interconnects most likely relates to how the cable shield & conductors are wired differently at the source and load ends.
With phono interconnects between a turntable and phono pre-amp, the interconnect capacitance matters a lot (cartridge load = interconnect capacitance + pre-amp loading capacitance).
For those looking to DIY their own interconnects, this wiring guide might be helpful. Note that RCA source / XLR load cables are wired differently than XLR source / RCA load cables.
https://www.grimmaudio.com/wp-content/uploads/TPR-Assemblies-pinout-sheet.pdf