This filter is not perfect so you'll have a few audio artifacts that you won't want in your final mix. Mixing with the original audio hides these artifacts some

This filter is not perfect so you'll have a few audio artifacts that you won't want in your final mix. Mixing with the original audio hides these artifacts somewhat. Using this filter also increases your audio mixing effort (you're mixing in a second vocal track) so it's easiest to mix the 2 audio tracks at constant levels then adjust when you hit an artifact. This is my personal preference on this style of audio mixing, and others who watched (and gave feedback) couldn't tell it was enhanced and had no difficulty understanding the speaker.