the original intent of acrylic platters was to clamp the LP directly on them without a mat - essentially making the cartridge "think" it's riding on a 1" thick LP (or so I read somewhere). I found that using a Funk Achromat on my acrylic platter does provide some sonic benefits. Funk recommends not using a clamp with the achromat which makes it a little more convenient too.
Funk Achromat
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Funk Achromat
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