From inventor Amanda Ghassaei:
These records were cut on an Epilog 120 Watt Legend EXT to a theoretical precision of 1200dpi (the kerf of the cut and some tricks I used to avoid crashing the laser cutter dropped the actual precision down by ~1/6). The audio on the records has a bit depth between 4-5 (typical mp3 audio is 16 bit) and a sampling rate up to about 4.5kHz (mp3 is 44.1kHz). So far I’ve successfully cut audio on wood (figs 1-2), acrylic (figs 3-4), and paper (figs 5-6), and I’m sure there are many more materials that would work.
More info at instructables.com/id/Laser-Cut-Record