An improved audio amplifier system can both reduce power consumption by supporting a standby mode and shorten wake time when resuming from the standby mode. The audio amplifier system may reduce power by entering a sleep or standby state in response to a command and/or detecting that an audio input signal is not received. Further, the audio amplifier system may use a burst generator to periodically or intermittently activate the power supply during standby mode. By periodically or intermittently activating the power supply, one or more of the capacitors may be charged. By charging the capacitors during standby mode, the time to wake from standby mode may be significantly reduced. In some cases, the wake time may be reduced by several order of magnitudes (e.g., from seconds to milliseconds).