suggestons on speaker cable that boost mid and upper bass

Jmcgrogan is absolutely right, his view has been my experience with many cables - it would take a full page to list all the cables I have owned and tried in my system.  Melbguy's suggestion sounds interesting - that is one cable I have not tried.

I have had full looms of PAD and KS.  I had venustus, corvus  IC's and for SC I had proteus provectus.  Had them for a long time (for an audiophile) but over time I found they did not add the body I was seeking with my Thiels.  Currently using KS Fascinations throughout and they seem to be a nice match as Thiels do not need help in the upper frequencies.  Considered Emotion but not sure you get that much more for the huge price difference.  I believe you get more at the frequency extremes but again, do not think I need it in my system.  

If you give KS a shot you probably want to start with Emotions - they have a good audition program and allow trade ups as well.

Bigdish, in my system PAD was more revealing than the KS Fascinations.  Not tipped up just more upfront and more detailed which over time became a nuisance with my Thiels.  That applies to the Provetus SC, which has been DQ'ed, and especially the Corvus IC.   Not sure solid core is the best option for Thiel.  The Corvus was PAD's entry into more revealing and detailed cables.  The highs were way over the top for me.  The Venustas on the other hand was the most balanced of the 3.  I ran a 5 meter IC between my preamp and amps.  I still have it but it is currently on the bench.

The KS Fascinations have a more laid back tone with a richer midrange, the Vensustas comes close in this area.  They are ultra smooth with a little rolloff in the upper frequencies and are more dense in a good way.   They also have a well defined bass, I wouldn't mind a little more definition in this area.  My bet is you get more of that as you move up the line.  They  remind me of Kimber 1011 and 1016 without the slight grain you get with those cables.  The real surprise when I went with a full loom were the PC's.  They work nicely on my amp and phone preamp.  They do not add too much bass and midbass which is my biggest complaint with aftermarket PC's.  Hope this helps - good luck.