Vega BT-2020 with 9v

The graph below shows the comparative battery life of various 9v batteries in a Vega BT-2020 body pack transmitter.

For years, most of the wireless audio industry have considered Duracell Procell batteries to be the best choice. Indeed, the best battery shown on the graph above is a Procell. However, the three Procell's tested were extremely inconsistent. Also, the four Duracell Copper Top batteries tested were the worst performers.

The most consistent and long lasting 9v batteries seem to be the Energizer industrial and Wal*Mart Everactive batteries. These gave consistent run-times that exceeded 5 hours, 45 minutes in a BT-2020.