I haven’t tried other cables; however, I would say my cables are fairly neutral. My USB cable from the MacBook to the DAC is an audioquest coffee. The interconnect, power cables, and speaker cables are DIY Helix Image. I would say they are extremely neutral with great imaging and texture that allows for great soundstage separation.
Also, other speakers don’t roll off like these in the same system. Could some of the old crossover parts be shot? Could the tweeters be tired even though they are playing?