I've ordered from both Amphigory and Arda before. I have swatch rings that match both sites.
Here's the thing: Amphigory and Arda use completely different color sets. Arda's colors are unique to them as far as I can tell. The majority of the wigs and fiber sold by Amphigory, on the other hand, use the same color scheme as New Look, Sepia, and most other Western wig manufacturers. On top of that, you're also trying to compare completely different fiber types.
To answer your actual question: I looked at my swatch for Arda's Dark Ash Blond (#029) and compared it against my New Look #24 swatch. They are VERY different. Arda's #029 is a blend of ash blond and a little bit of auburn, so the final color is much more "ashy". Amphigory's #24 looks like it's a very subtle blend of medium and light blond. When the two swatches are next to each other, there's a stark difference.
But even if some fairly close color matches do exist, I honestly wouldn't try to combine products from Arda and Amphigory to begin with. Arda uses hiperlon fiber, which isn't nearly as shiny as kanekalon. Under a flash and/or in certain lighting, the kanekalon fibers get really glossy shiny whereas the matte hiperlon would barely reflect light at all. You'd end up with a rather obvious franken-wig.
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