Class D amplifiers, often called “switching” or “digital” amplifiers, represent a highly efficient audio amplification technology. Unlike traditional Class A or AB amps that use linear conduction to boost signals, Class D amps operate by rapidly switching output transistors on and off at high frequencies (typically 200 kHz to 2 MHz). This pulse-width modulation (PWM) technique creates a series of pulses whose average voltage mimics the input audio waveform, which is then low-pass filtered to recover the clean signal.
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