What is DC offset and what does it do?
DC offset is the average vertical offset from 0 dB of the recorded waveform. This is normally visible only in silent sections of the waveform. Most sound cards have some DC offset when you are recording. Usually you cannot see this offset unless you expand the vertical gain nearly to the limit and look into a silent portion of the recorded waveform. Virtually all sound cards have some DC offset. DC offset can cause problems in compressing voice files using the Intervoice ADPCM format. It also causes errors when you are trying to measure the noise floor of a recording. A preset to remove DC offset is found in the Intervoice example batch files for Sound Forge and in the Vox Studio Batch Conversion tool.
