I owned a Calipher signature until I sold it about few weeks ago I been listening Apogee speakers since the 90's.
SYMO speaker cable was the cable for apogee but you cannot find it anymore but, The good news is you can tweek your diva which I did with my calipher. I audition a lot of speaker cable I mean a lot!! try using the wireworld eclipse 5 speaker cable for your mid and high and use the PS audio xtream bi-wire for your lows and tell me if you hear the difference. I did enjoyed it for years believe me you will save a lot of money by changing speaker cables if you see the cables I mentioned you know what I'm talking about. May I ask what amp are you using for your diva? if you have any questiongs e-mail me you are more than welcome.