Controlled charging and use of power source

An apparatus comprising:

• an amplifier to amplify an audio signal to be output by an acoustic driver, wherein the amplifier changes an amount of power required by the amplifier to amplify the audio signal in response to receiving a signal indicating an availability of electric power to the amplifier;
• a first power source capable of providing the electric power required by the amplifier when at least partially charged;
• a second power source that is intermittently available, wherein the second power source is unable itself to provide the electric power required by the amplifier, and wherein the second power source is selectively employed to charge the first power source;
• a capacitive element;
• and
• a power converter interposed between a pole of the amplifier and the first and second power sources, imposing a limit on an amount of current permitted to flow through a portion of the power converter to thereby limit an amount of current permitted to flow through the load, causing the capacitive element to charge at a time where the load attempts to draw a relatively small amount of current, and causing the capacitive element to discharge at a time where the load attempts to draw a relatively large amount of current such that the load is supplied with the relatively large amount of current as the capacitive element discharges.

A method comprising:

• setting a first limit on an amount of current permitted to flow through a portion of a power converter such that a capacitive element is caused to be charged when a load draws a first amount of current through the portion of the power converter and such that the capacitive element is caused to be discharged when the load draws a second amount of current through the portion of the power converter;
• awaiting a signal indicating an availability of a detachable power source;
• and
• in response to receiving the signal indicating an availability of a detachable power source, setting a second limit on the amount of current permitted to flow through the portion of the power converter such that the capacitive element is caused to be charged when the load draws a third amount of current through the portion of the power converter and such that the capacitive element is caused to be discharged when the load draws a fourth amount of current through the portion of the power converter, wherein the second limit is higher than the first limit, wherein the third amount of current is larger than the first amount of current, and wherein the fourth amount of current is larger than the second amount of current.