Use Multipressor in Logic Pro for iPad
The Gain Reduction field actually shows the amount of overall gain change—not merely the gain reduction—as with a standard compressor. The display shows a composite value consisting of the compression reduction, plus the expander reduction, plus the auto gain compensation, plus the gain make-up.
The Compression Threshold and Compression Ratio parameters are key to controlling compression. Usually the most useful combinations of these two settings are a low Compression Threshold with a low Compression Ratio, or a high Compression Threshold with a high Compression Ratio.
The Expansion Threshold, Expansion Ratio, and Expansion Reduction parameters are the key parameters for controlling downward expansion. They determine the strength of the expansion applied to the chosen range.
Adjusting the Response parameter between Peak (0 ms, minimum value) and RMS (root mean square −200 ms, maximum value) is dependent on the type of signal you want to compress. An extremely short detection setting (under 50 ms) is suitable for compression of short and high peaks of low power, which do not typically occur in music. Using a higher value of around 200 ms measures the power of the audio material over time and thus works much more musically. This is because human hearing is more responsive to the overall power of the signal than to single peaks. As a basic setting for most applications, a value of 100 ms is recommended.
The Master Gain knob sets the overall output level. Set Lookahead to higher values when the Response parameter is set to higher values (around 200 ms). Turn on Auto Gain to reference the overall processing to 0 dB, making the output louder.
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