Certainly longer xlr. As for the speaker cable, do not do less than 5-6ft even if the length required is something like 3ft. You want to allow the speaker cable to do their job. Too short of a run and you can get added noise into the speaker because of the fact that it is so short, as speaker cable has an ability to dissipate unwanted noise over longer runs respectively and not going too long where you get signal loss. If you are going to keep them super short, be sure to use a smaller awg cable as to reduce signal to noise. It’s an issue some powered speakers can run into. Cables are like tone controls, longer and shorter runs of identical speaker cable can sometimes sound different on the same set up.
Long interconnect or speaker cable
My room configuration requires that my rack is off to the side of my speakers. This means I need to run 20 feet of speaker cable (Wireworld) from my Mc mono blocks. This makes high end speaker cable cost prohibitive.
I was thinking I could move the amps next to the speakers, have short higher quality speaker cables, and then a long run of moderately priced XLR interconnects from my preamp.
So, all things being equal, what’s better for SQ, a long run of lesser XLRs or speaker cables?