Speaker cable suggestions

Thanks for the help everyone. As for length, I was thinking about 8'. I was upgrading with the midbass first and then making my way up the chain. I have to start somewhere. I'm finding that 50 Hz is being overamplified in my system and I wasn't sure if it was the room, cables, speakers, or system in general.

Why not get some cable where u can bi-wire on the speaker terminal side. Or simply, don't bi-wire at all. Just take out the worse link in your system, which is probably the Sonance cable.

For a value priced speaker cable check out Kimber 8xx or 4xx many bi-wire with 8xx going to the mid-woofer and 4xx going to the tweeter. I used a long(36 foot pair) of Kimber 8TC for a long time and it sounded pretty good for the money, plus it is super easy to sell kimber and either break even or make money(as long as you buy used to begin with). You could also use a single run of 8TC or something similar and split it into 2-4TC runs while retaining the original braid.
~Tim

Just so everyone knows, I am not biwiring here, only biamping. I could use the same cable on tweeter and midbass, but I have different amplifiers on each. So I have to find cable that works well with both amps. Currently I am working on the midbass cable, once that is complete I will work on the tweeter cable.

Unless you sit your amps very far apart, you can double biwire.