FEEDEQ_PREAMP_SIGNVAL
(FEEDEQ_PREAMP_SIGNVAL(FEEDEQ_GAIN_MIN) * \
(FEEDEQ_PREAMP_SIGNVAL(FEEDEQ_GAIN_MAX) * \
FEEDEQ_GAIN_STEP)) + (FEEDEQ_PREAMP_SIGNVAL(v) * \
FEEDEQ_GAIN_STEP)) + (FEEDEQ_PREAMP_SIGNVAL(v) * \