Buy Decision Audioquest vs. Audience

Audience makes good stuff and that model uses the OCC copper (Ohno), but it's normally all stranded wiring from this company.  The Rocket 44 is combination of PSC and PSC+ copper (Audioquest's Perfect Surface Copper, which is very close to OCC anyways).  Rocket also has solid-core conductors (which are better) that span multiple awg sizes.  The only downside is that Rocket sometimes has those silver-plated spades/bananas which can cause the system to be too bright.

I would recommend buying the Rocket 44 "PREMIUM No Frills" model from Audio Advisor.  They have a deal with Audioquest where they terminate custom lengths of the Rocket 44 with their own connectors.  The PREMIUM version uses the better gold-plated copper Pangea spades and bananas.

Oh, one more detail.  The Rocket 44 is only a 13awg speaker cable, so I do not recommend doing a bi-wire termination.  That will split the cable into a 15awg / 16awg wire set.  If your speaker has four binding posts for bi-wire, I would connect the Rocket 44 to the upper binding posts and use a jumper cable to connect the lower binding posts.

Or buy two sets of Rocket 44.

@dustsailor - it is more likely that you are hearing the gold-plated terminations.  Most people don't realize that the terminations are just as important as the wire.  I'm running Rocket 44's with Furutech rhodium spades and I do not have any problems with soft bass or treble extension.  The gold-plated terminations will have the effect you talk about.  Silver plated will have more of a bright sound.