VBrick Systems 7000 manual Audio

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Audio

The audio circuit on the H.264 encoder uses mixed signal technology (a combination of analog and digital signals). The encoder has two audio input connectors labeled Main and Aux. The input signals can be either balanced or unbalanced and each has a usable voltage range up to 10 dbU. Various channel configurations and bit rates can be set on the Audio/ Video Configuration > Audio page. The encoder provides controls for mic level vs. line level balanced mode support, input gain/attenuation, automatic level controls, and other advanced audio features. The encoder supports three types of electret microphones:

•Electret Condenser, battery operated or plug-in power (SoundBlaster style)

•Dynamic type balanced or unbalanced

•Externally-powered phantom types and otherwise amplified types such as wireless.

The microphone input is automatically boosted by a pre amplifier. The pre-amplifier provides a selectable 16 or 32 db of gain (boost). Various configuration parameters control how the input signals are conditioned as well as how the resultant audio is compressed. The audio input signal parameters define how audio is connected, what the signal ranges are, the style of electrical interfaces, and the number of channels connected to the device. Audio encoder parameters define how the audio will be compressed and are used to control the bit rate. The bit rate directly affects the audio quality levels and determines the range of audio content that can be handled.

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