Pass x-350 and Dunlavy SC-IVa - what speaker cable

I have the Dunlavy SC-III's which I absolutely love. I am using the Dunlavy cable DAL which is a perfect neutal match for these speakers. I have several sets plus Dunlavy DAL interconnects which serve me well too! My bother-in-law also uses the same DAL cables on his Dunlavy SC-V's and
SC-VI's.

You may want to try a Synergistic Research cable. I have had good luck with the Research Ref and Designers Ref. Res Ref on Low Freq input and Des Ref on High Freq. Either by themselves, even without bi-wiring, will sound great. But, when one has an extra pair of cables, one must find a use for them.;-) The low end on the SC-Vs was as good as any other purpose I could find.

The Dunlavy cables mentioned above work very well with his speakers. And my bet is, although I haven't heard the combination, that the Kubala Sosna cables, particularly the Emotion line, would be an excellent match for your equipment and speakers.