You need balanced amps to make any difference with balanced cables. Necessity is determined by RF noise in your playback space and sensitivity to it of your electronics.
Need 25 foot interconnects
I just moved around my equipment so that the rack with the preamp and digital sources is on the left side of the room and the monoblock amps are just behind the left speaker on a short platform on the floor. I’m using a 15’ RCA interconnect right now, but want to move each monoblock to just behind each speaker — which means I need a longer cable. The monoblocks are unbalanced RCA input only but my preamp can do balanced XLR or unbalanced RCA out. Would a balanced XLR cable plus an XLR to RCA adapter work for this setup and be my best option? Or should I just get a Belden (or similar) 25’ unbalanced RCA interconnect? Or is there a better option?