Other bsp
stfx_gm_rng_convolve_voiceplugin_test-26Apr2022

float r1 = (lfsr_randf(&voice->lfsr_1, 2.0f/max/) - 1.0f) voice->mod_seed1scl_cur;
float r2 = (lfsr_randf(&voice->lfsr_2, 2.0f/max/) - 1.0f) voice->mod_seed2scl_cur;
float r3 = (lfsr_randf(&voice->lfsr_3, 2.0f/max/) - 1.0f) voice->mod_seed3scl_cur;
float r1mr2 = (r1 - r2) voice->mod_scl1_cur;
float r2mr3 = (r2 - r3) * voice->mod_scl2_cur;
out = r2mr3 - r1mr2;

then add a LPF + HPF (20Hz), and modulate !