Patent ID: 9681213
Date: 2017-06-13
CPC Classifications: G10K,H04R

Claim:
1. A headphone device, comprising: an electric input terminal for receiving an electric audio signal; an electric energy storage device; a charging device coupled to the electric input terminal and the electric energy storage device and configured to charge the electric energy storage device with electric energy from the electric audio signal; an audio processing device configured to receive the electric audio signal and to generate an electric audio output signal based on the received electric audio signal; and an electroacoustic transducer coupled to the audio processing device for outputting an acoustic signal based on the generated electric audio output signal; and wherein the audio processing device is powered by electric energy from the electric energy storage device; and wherein the audio processing device is configured to control a volume of the electric audio output signal at a constant level depending on a charging level of the electric energy storage device to compensate for variations in volume output of the headphone device due to a varying amount of energy derived from the received electric audio signal for charging the electric energy storage device.