About the balanced connection
Unbalanced connections have commonly been used for portable audio devices. This connection method works as L+/R+ signals go through an amplifier and L-/R- signals go through the ground. Devices with unbalanced output are normally less expensive and easy to handle compared with the balanced output devices, but unbalanced connections cannot prevent noise occurrence since noise can be picked up if there is a difference in voltage potential on the ground of the chassis of your device.
One of the biggest advantages of balanced connection is that it can stabilize the voltage potential by transmitting the signals as the opposite phase, L+/L- and R+/R-, to an amplifier. Not only does this prevent the signal distortion caused on the ground, but also eliminates noise and hum with opposite polarities relative to each other. As a result of this, balanced connections brings you clear sound with noiseless signals and improved crosstalk.