Quantize menu
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Main Page > Reaper Documentation > MIDI Editor
The top radio button allows us to quantize selected events or the whole sequence. This can certainly come in handy if you just need to quantize a certain off section, or perhaps just the hihats of a drum section. This is an example of a non quantized sequence:
The next control, Quantize Positions, moves the start position of the midi events to align to the value you set.
Next, Quantize Length extends or shortens the end position.
When both are selected, here is the result:
The strength button is rather intuitive; the lower you set it, the less 'magnetism' the grid has to the midi notes.