ECC99

The ECC99 is a modern dual triode designed by JJ Electronic specifically for audio driver applications, with no direct vintage equivalent. It features a mu of ~22 and unusually low plate resistance (~2.4k ohms per section), giving it exceptional current delivery and load-driving capability for a small-signal tube. The ECC99 can swing large voltages while sourcing significant current, making it an ideal driver for power triodes like the 300B or 2A3 in transformer-coupled or interstage-coupled designs. Its modern design and robust construction make it a practical choice for new amplifier designs that need a strong octal-based driver stage.