One more file of the PHYS engine's DSP is ported from Emilie Gillet's eurorack code
<https://github.com/pichenettes/eurorack> (MIT):

- src/phys_symp.c, the sympathetic strings of the SYMP model: Rings, rings/dsp/part.cc
  (RenderStringVoice: the sympathetic strings and their tuning, damping and brightness) and
  rings/dsp/string.cc

Ported to fixed-point C for Felucca, 2026. The ported file stays under the MIT licence below;
the rest of Felucca is GPL-3.0-only (LICENSE). "Rings" names the source only; no Felucca model
or preset is named after it.

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Rings, copyright 2015 Emilie Gillet (emilie.o.gillet@gmail.com)

Published under the MIT license:

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