As the signal voltage in the hot line increases the cold line s signal voltage decreases precisely mirroring the hot signal in reverse.
Balanced cable line out.
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.
Balanced cables have three wires inside the plastic casing.
In balanced signal paths there is a second signal conductor referred to as the cold line.
But what makes a balanced cable special is the way the gear utilizes that.
In both cases one jack is normally used for each audio channel left and right.
Balanced cables cost a lot more than unbalanced cables sometimes even twice as much simply because of the added benefit they provide.
A balanced cable by contrast has three conductors in the connector and three wires in the cable.
However this did not become widespread until repeater amplifiers became available.
However if you re out to save money then unbalanced cables might be your best choice especially if you re just using really short ones.
Open wires on the other hand with their lower capacitance had been used for.
The hot and cold lines transmit identical signals that are 180 degrees out of phase with each other.
As in the unbalanced cable the ground wire still surrounds the signal wires and is used as a shield against interference.
For an unamplified telephone line a twisted pair cable could only manage a maximum distance of 30 km.
The cable construction used for balanced telephone cables was twisted pair.