TAS6424MS-Q1 Class-D Audio Amplifier Texas Instruments TAS6424MS-Q1 Class-D Audio Amplifier is a four-channel digital input Class-D audio amplifier that implements a 2.1MHz PWM switching frequency. This enables a cost-optimized solution in a very small PCB size, full operation down to 4.5V for start/stop events, and exceptional sound quality with up to 40kHz audio bandwidth. The output switching frequency can be set either above the AM band, which eliminates AM-band interferences and reduces output filtering and cost, or below the AM band to optimize efficiency.