SPHINX 101 - Simulated Analog Circuit Physics
Analog Realism
https://analogrealism.com
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  Transformer physics:

  1.  Jiles-Atherton magnetic hysteresis with flux integration - the core is driven by
      integrated flux (V/f law), producing frequency-dependent saturation that matches real
      iron
  2.  Four core material models with distinct saturation curves, permeability, coercivity, and
      remanence per material class
  3.  Winding asymmetry producing even-order harmonics whose magnitude varies with transformer
      model
  4.  Bias-DC flux walk - program-dependent DC magnetisation offset producing
      session-responsive even harmonics
  5.  Remanence - the core retains a fraction of its magnetisation during silence, starting
      each new phrase from a non-zero magnetic state
  6.  State-domain Bertotti dynamic core loss - eddy current and excess loss terms that resist
      rapid flux changes like physical friction in the iron
  7.  Signal-dependent copper winding loss with thermal DCR rise over the session
  8.  LC resonance from leakage inductance and winding capacitance, per model, entering the
      measurable band at high sample rates
  9.  Signal-presence-gated demagnetisation with remanence target
  10. Inter-transformer magnetic coupling through chassis proximity

  Power supply:

  11. Shared rail sag with asymmetric attack and release, soft-clamp asymptotes on seven
      consumer sites
  12. Conduction-gated reservoir ripple with rectifier harmonics and mains frequency selection
      (50/60 Hz)
  13. Differential per-channel rail sag under asymmetric stereo
  14. Series-pass voltage regulator model with per-topology PSRR
  15. Signed ground-return injection carrying the signal fundamental through per-topology
      chassis impedance

  Active electronics:

  16. Ebers-Moll BJT with Class-AB crossover emphasis and thermal junction bias shift
  17. Koren vacuum tube with grid-current blocking at millisecond charge rate and
      hundred-millisecond discharge
  18. Child-Langmuir 3/2 power-law diode detector
  19. VCA with control-voltage feedthrough and class-AB low-level crossover distortion per
      manufacturing grade
  20. Jiles-Atherton EQ inductor hysteresis with genuine path-dependent inductance modulation
  21. Capacitor dielectric absorption with multi-time-constant charge re-release per
      dielectric type
  22. Per-topology amplifier slew-rate limiting
  23. AC-coupled output path - gain-cell DC offsets never reach the output, whether the
      output transformer is engaged or not, matching hardware output coupling

  Dynamics:

  24. Variable-Mu feedback compressor with gain-reduction-coupled harmonic generation
  25. Program-responsive HF soft clipping in Tube and DPX modes

  Environment:

  26. Cross-channel crosstalk with frequency-dependent shaping
  27. Per-instance manufacturing tolerance variation from seed
  28. Filtered-noise 1/f thermal drift, aperiodic and per-instance
  29. Program-responsive thermal self-heat with fanout to transformer permeability,
      transistor bias, tube transconductance, and core loop parameters (k, a, c)
  30. Physical component warm-up on instance creation
  31. Current-scaled shot noise on five Class-A device stages
  32. Per-topology 1/f noise spectral shaping across the full audio bandwidth
  33. Channel-independent noise floors - each channel draws its own noise stream while the
      stereo pair shares matched component tolerances, so the floor sums to mono and nulls
      the way two real devices do
  34. True Gaussian noise statistics - the modeled thermal floor carries the statistics of
      real thermal noise rather than a uniform digital approximation