A sensor includes a flexible wafer substrate and an oscillator provided on a principal surface of the wafer substrate, and the oscillator deforms when an external force is applied to the wafer substrate. The LED light bulb further includes a bulb circuit board mounted upon the bulb base and extending upwardly therefrom. In a master device side, a PCM signal is converted into ADPCM data by an ADPCM encoding unit. The master private key is stored in protected storage within the security subsystem such that the master private key is inaccessible outside of the security subsystem. Techniques for representing multiple channels of an audio clip as a single waveform and caching waveforms are also provided.