I'm using Tanstaffel brand strings on my generic 12-string and it stays in tune very well. But they're not really called TANSTAAFL. They're called some brand I have forgotten. Helpful, huh?? :>) Lemme think.....Thomastek Infeld, that's the name I was looking for. You can find them at JustStrings.com, and I am very happy with them.

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