Any engineer knows that you can never have too many little black utility boxes around.
Radio Design Labs has survived for decades knowing that and supplying such utilitarian boxes.
The latest is the RU-AFC2 stereo audio format converter.
The duty of the bidirectional RU-AFC2 is to turn unbalanced (consumer) audio into balanced audio and vice-versa. RCA, XLR and terminal contacts are used.
There is a mono sum output for delivering audio to patch panels or speakers. The front panel has level trims and simple LED meters. The box is 1/3 RU.