The following article will guide you through the basic steps for removing vocals or an instrument:
To find the part that you want to eliminate, lower the "INSIDE LEVEL" slider to reduce the volume of the sound inside the red frame.
NOTE: The volume of the sound is indicated by color. The color will appear as follows according to the volume:
Black (quietest) ... Blue ... Green ... Yellow ... Red ... White (loudest)
By dragging the red frame, move it to the location at which you no longer hear the part that you want to subtract--or to a point where the majority of the part is no longer heard.
You can use the SHAPE to switch the frame between a rectangle or a circle and drag the edge of the frame to adjust size. The choice of shape and size will be a combination of listening to the difference each makes and looking at the R-MIX grid for the hottest points in white, red and yellow.
NOTE: If you make the shape too large, other parts will also become inaudible.
ADDITIONAL NOTE: R-MIX analyzes the imported music according to frequency, panning (left to right) and volume. For some songs, the frequency or panning of the musical parts are indistinct--due to how the song was mixed by the sound engineer (e.g. the vocals might have a lot of effects all over the mix). Because of this, you might not obtain the results you expect from all songs.