User's Guide

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DC offset meter in Analyst

A. DC offset meter

The DC offset meter is a bi-directional bargraph meter that lets you detect DC offset in audio. There

are various ways DC offset can be introduced into a mix. DC offset can come from recording

sources, software instruments, or it could be present in imported wave files. Although the effect of

DC offset is normally impossible to hear, it can produce some very unwanted side-effects, including:

• Loss of apparent loudness in mix. Because the audio in the final mix is skewed positive or

negative, you run out of headroom sooner and must reduce gain to compensate.

• Loss of quality when using mastering compression. Because the waveform is off-center, a

compressor will asymmetrically alter the waveform producing low frequency harmonic distortion.

• The DC is essentially sub-sonic information that will affect the lowest band of any multi-band

processing.

To check your audio for DC offset in real-time before exporting/mastering, patch Analyst in a mix

bus. Ideally, the DC offset meter should appear as a small dot in the middle of the scale. As the DC

offset in the input signal moves away from 0dB, the DC offset meter bar lengthens up or down,

indicating either a positive or negative DC offset. As the DC offset becomes larger, the color of the

meter bar changes from blue to red. The scale of the meter is -50% to +50% dbFS.

For information about removing DC offset, see the “Removing DC Offset” online Help topic.