suggestons on speaker cable that boost mid and upper bass

Thank you melbguy1 for your kind suggestions. Sorry I forgot to mention my budget. I have no experience in Siltech cables, but my budget is only about 6000 dollars, but I would rather not to spend so much if possible, The Royal Signature is just too much for me. I have heard many many good things about Siltech cables. 

Thank you all for your suggestions. Mich appreciated.  For ICs, I am using Stage III Concepts Gryphone from SCAD to preamp and PAD 25th Anniverary from preamp to amp. Both are great ICs. Thats why I think my speaker cables are the weakest link. I am also thinking of copper wires. Anyone has experiences in PAD and Kubala Sosna speaker cables? I heard they have great density and flow and are a bit warm. Interested in PAD Neptune or Kubala Sonsna Emotion or even Elation. A pair of Dominus are just too much when buy new. Been looking for second hand pairs but not available at the moment. How does Cardas Clear Beyond sounds? 

Thanks pops. I would also like to try Kubala Sosna cables. :-) What's the differences in sounds between KS and PAD in your opinions?    
   
Yesterday when I tried matching different power cords with each components, I found out that a silver power cord of mine plugging to a word clock was the problem.....  When I used a copper power cord on the clock the sounds were much more natural, though I definitely still want more lower mid and upper bass.    
   
Thanks ebm. Stealth V14 is just too expensive to me.  
   
Thanks jmcgrogan2.