Conventional amplifier usually uses ground power supply as a signal reference. So it caused the conventional amplifier has IHM noise (Interval Hum Noise Modulation). The system of amplifier must be really balance from the input to output in order to minimalize the noise. This research make a balance amplifier class AB push-pull with power rms 120 Watt and frequency bandwidth between 50Hz to 10kHz. This amplifier use complementary pair as a current-driver.
The Experimental result show that the balanced amplifier has power output only 110 Watt, 22 Volt operating voltage and have a bandwidth from 30 Hz until 15 KHz, gain 13,5 dB. Beside that the Experimental result, balanced power amplifier also has very small IHM compared with unbalanced power amplifier.