How to implement a symmetric audio output on a small audio device using a single supply battery voltage only.
I like to drive symmetric XLR inputs, and use a symmetric connection for noise suppression on long cables. I have a DAC sporting two channels, thus I can create a positive and negative audio signal directly.
But how to connect the output?
- Is it ok to always have the symmetric lines with some DC offset in respect to GND? I guess not, because there may be adapters to asymmetric inputs that will just short the negative line to GND if I'm understanding that right.
- So is it safe to assume that a symmetric input will place my circuit in a safe DC range by it's own, so I can just connect positive and negative, and leave GND open?
- Or is it still needed to place capacitors, and if, on which lines? Positive and negative only? Or just on GND?