Connect the harmonizer to the amplifier using an audio cable. Insert the audio cable into the audio output on the harmonizer and into the effects loop send on the amplifier. Insert a second audio cable into the effects loop return on the amplifier and into the input on the harmonizer.
Plug the harmonizer and the amplifier into a power source. Insert an instrument cable into the guitar jack and the other end of the instrument cable into the amplifier input jack socket. Turn on the amplifier and make sure the volume is low to prevent any loud popping sounds from damaging the speaker. Turn on the harmonizer.
Turn up the volume on the amplifier to an audible level and test the sound by playing some notes on the guitar. Select the effects on the harmonizer and proceed to play the guitar to test out the sounds. Make adjustments to the harmonizer's effects and voice selections to enabl test a variety of different sounds and harmonies.
Attach a microphone to the amplifier using a microphone cable inserted into the second channel input. Sing through the microphone and add different harmonic intervals form the harmonizer. Once the harmonizer has been tested to a satisfactorily standard, turn off the unit and the amplifier.