Balanced cables balanced cables have three wires inside the plastic casing.
Unbalanced cable into balanced input.
An xlr connector configured for an unbalanced output.
The cd player has balanced outputs on xlr jacks but not dual dacs per channel.
Unbalanced line level connections are usually implemented with rca jacks for audio while balanced line level connections typically utilize dual 3 pin xlr jacks for both the input and output.
The diagram above shows how the cable works.
Having cables with this kind of output makes it easy to directly connect unbalanced sources such as guitar effects directly into recording gear daws and signal processors with balanced inputs.
Even if you plug a balanced cable into an unbalanced output jack the signal will be unbalanced see the downsides of unbalanced above.
Where it gets a little more custom so to speak is ts or rca outputs to xlr inputs for example.
The cd player creates the balanced signal by converting the unbalanced signal from the single dac to balanced with a circuit called a phase splitter the audio signal has just been subjected to an additional active stage usually an op amp.
A balanced audio cable has a ground wire but it also carries two copies of the same incoming audio signal sometimes referred to as a hot positive and cold negative signal.
A balanced circuit needs to be three wires positive negative and ground all the way through.
In both cases one jack is normally used for each audio channel left and right.
The structure of a balanced audio cable is similar to an unbalanced cable with one addition.
If you start with an unbalanced source and an unbalanced cable two wires that signal will remain unbalanced when you plug it into a balanced input.
You can with some caveats.
The signal wires pass an identical audio signal through each wire while the surrounding ground wire works the same as in unbalanced cables shielding the signal wires from external electronic interference.