Kenny's - Look Ahead Compressor

Duplicate the vocal (or any)track

Shift it a few ms. earlier in time.

Set the output of the duplicated track to an unused buss.

Then put a compressor on the original track.

Set the compressors key input to the bus your using for the duplicated track.

The compressor will now respond earlier to input which will eliminate the pumping sound.

Enjoy.

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