Quad Saturator: 4-Band Saturation Plugin by IK Multimedia

Quad Saturator divides the signal into four frequency bands, and each band has its own controls for drive, tone and level. Five saturation algorithms are available, so you can give low, low-mid, high-mid and high frequencies distinct distortion characters within one plugin.

Band power and solo switches let you audition or isolate a single band while you set it. A bleed control smooths the blend between neighboring bands, which helps avoid hard transitions where the bands meet.

Envelope followers let the saturation respond to the level of the incoming audio. Attack and release times are adjustable, so you can tune how quickly the effect reacts to transients and how long it lingers afterward.

The Output section blends between dry and wet signal and provides overall level control, so you can keep the saturated sound in balance with the original track.