Do Jumpers make an audible difference?

It depends upon the loudspeaker, but why would you not use Nordost?

Ime, huge difference as when compared to the supplied buss bars/plates.

Best is to stick within family brand to achieve more harmonious/coherent tonal balance.

Buy best you can - Say if using ZPython SC, getting the ZAnaconda jumpers would make a worthwhile jump esp. if use for mid-high connections.

Then again improvement is highly dependent on your speaker's x-over. Are they true bi-amp/bi-wirable design or cosmetic one ie.split at terminals only. If the later, I would not worry too much about it. *Also, your system's resolution will play a big part as to the result gained.

There are a couple of known popular methods going about this - cross/diagonal jumping.. But I attained best result still using the conventional method i.e.main SC to low +- and (better) jumpers to high +-.

Bottom line is there are no guarantees. What works well in one system will not necessarily sound the best in another. You have to try it for yourself and decide what sounds the best. Perhaps you can demo a pair from where you purchased the loom of Shunyata products from?

Try using some junk jumpers for a downward comparison to see how much of a difference may be possible. Better yet, have someone else put only one, or not, in and see if you can identify it.