Reduce low level amplitude oscillations by frequency

[Ploki]

Are you sure its just tremolo and not also vibrato? (Pitch fluctuation)

It’s hard to remove that because fluctuating intensity in a voise also changes harmonic content usually, not only amplitude and pitch.

[pluginnow]

Are you sure its just tremolo and not also vibrato? (Pitch fluctuation)

It’s hard to remove that because fluctuating intensity in a voise also changes harmonic content usually, not only amplitude and pitch.

You are both right. It could be vibrato too..

I know auto-tune has a tool for it.

If you listen that video carefully, you'll find some very smoothed vocals.

[CinningBao]

There are a tonne of mostly-quite-expensive tools you can use to remove vibrato (pitch modulation) like Autotune (try graphical mode, it has a bit more manual control of each note), Melodyne, ReVoicePro.. maybe that bx_tuning thing? Vari-audio in Cubase?.. but as Ploki says, especially with voices, you can't really remove/flatten one without the other still 'affecting' the voice. Tremolo is a bit harder; even compressors with a 'hard setting' will exhibit some influence on the sound even if they can flatten the dynamics. And you'd need to automate it to a degree since if you have on the whole vocal, .. well you'll ruin all the dynamics of the performance.

Multi-band compressors aren't going to remove the energetic waves which are amplitude modulation; sure they might kind-of flatten the dynamics a bit, but because a voice is 'tight fleshy folds be vibrated by a controlled flow of air' (my crude definition for this example), the sound the performer makes at low flow rate is different to the sound a high flow rate makes, the quiet and loud bits will have a different tone, and you can't remove or flatten or whatever, that.

I would set your expectations lower. And maybe think more carefully about what you want to achieve, and why.