Bi-wiring with different cables for HF and LF?

I've tried it. Unless you really need some type of "band aid" fix for a problem, its usually a really bad idea. If you have really revealing components, you should easily be able to hear 2 different cables.

"But since plain stranded cable has somewhat fallen out of favor, I wondered if I might be able to improve the definition and articulation of my bass with a different cable for the LF run."

Who cares. If they work for you, use them.

I think you are asking too much of your cables. Even though cables can sound different from each other, you have to remember they're still passive components and can only do so much. A well designed cable should give you excellent sound in all areas. If you're not happy with your bass, a much better solution would be to focus on your active components. Upgrading your source, preamp or amp is more likely to fix your problem.

"Richard Vandersteen also says its a bad idea."

He's right. I was using Vandersteen speakers when I experimented with using different cables on the top and bottom. Its kind of hard to explain, but the system just sounded wrong. You really have to hear it for yourself.

If you are going to experiment using silver cables for your bass run, I'll offer a suggestion. Since silver is expensive, and you don't have your mind made up as to what will work best (I make that assumption based the fact you are experimenting), I would to borrow some silver cables if you can. Generally speaking, what people like or dislike about silver cables, tends to be in the high frequencies. For low frequencies, its very possible that using silver offers no advantage over copper.

If you try copper, as well, you may want to compare solid core vs stranded. Again, generally speaking, stranded seems to offer better bass performance over solid. Thats not the only factor, but something to keep in mind.

Ozzy,

"I don't agree that stranded copper provides better bass than solid wire."

I meant that as just a general statement based on my own experience. You are correct, though. I'm sure some solid core designs may perform better. I prefer SC myself.