Recommendations for solid core speaker wiring?

Look no further Paul Speltz Anti cables..........

Not exactly solid core, but check out Goertz AG series speaker cables.

Another Speltz vote

www.anticables.com

From a theoreticall/electrically pure point of view, no one can really argue with the Speltz solution. They are available only in one gauge however, and unless used in short runs (I'd say under 1.5 M or 4.5 ft.) could be susceptable to mechanical vibration and RFI pickup. The important thing is that for $10/foot, you can find out if solid core (or minimal strand cable0 is what you need.

If you want solid core cable that does everything right unconditionally, then there are a number of good brands such as Audience, Audioquest, Virtual Dynamics (the best price/performance ratio), and the most expensive (and very best performance) would be the new Purist Audio Design Proteus Provectus (I cried for a week after returning the demo pair ;-(
.

I can vouch for the Morrow Audio cables. They are built using numerous, small-gauge, solid-core-copper, silver-coated coductors, so they meet your design request perfectly. IMO, the new SP3 Reference speaker cables are an incredible bargain at $299/pair.