Connect the signal you would like to convert from unbalanced to balanced to the Di4 via a 1/4-inch unbalanced jack to one of the channel inputs on the front panel of the unit. Connect an XLR balanced cable to the corresponding channel output on the rear of the Di4 and connect to your chosen destination. If the input signal strength is too high you can depress the 20dB pad. If there is an ground (earth) loop hum you can remove by depressing the earth lift switch.