Here’s a simple Di Box that you can build. In case you don’t know the purpose of Di Box, it is used to connect unbalanced output to balanced inputs. For example, a guitar has unbalanced output and a mixer have balanced input. Balanced lines are used for long cables audio because it is able to cancel noise on long cables.
About the Circuit
The circuit use an NPN general purpose transistor. You can use any general purpose transistor here similar to 2N2222 transistor.
Simulation
The positive output(emitter side) has slightly higher gain because emitter current is slightly higher than collector current. The difference is minimal and may not be an issue.
