Ventricular depolarization and repolarization processes are discussed. including their differences and heterogeneity both in patients with a healthy/sick heart. a matter of ranges. Measurements expressing the characteristics of ventricular repolarization are analyzed: the QT interval and other even more reliable measurements such as the TPEAK-TEND interval. https://www.roneverhart.com/Turbosound-TS-18SW700-8A-18-Low-Frequency-Loudspeaker-p31480/