A bipolar ionizer comprising an electronic circuit, microprocessor, and step-up transformer providing high-voltage signals to carbon-fiber electrodes producing bipolar ion concentrations greater than +/−200 million ions per cubic centimeter. The bipolar ionizer monitors, reduces, and converts high-voltage signals to feedback signals used by the microprocessor to vary a frequency and a duty cycle of a digital signal to control an excitation signal for a step-up transformer output voltage to consistently maintain an unbalanced high-voltage output ratio less than 80 percent, balanced bipolar ion concentration ratio greater than 80 percent, and zero ozone concentration over a range of electrical signal inputs. The microprocessor calculates and reports bipolar ionizer concentrations based on feedback signals. The microprocessor monitors concentrations of Volatile Organic Compounds (VOCs) in an airflow serving the bipolar ionizer and adjusts the positive/negative DC high-voltage signals and bipolar ion concentration when VOC concentrations are above a threshold.