Overdrive

Bitsmacker

Bitsmacker is a free overdrive and saturation Audio Unit plugin developed by Meatscience. Compatible OS(s): macOS.

Bitsmacker is a digital distortion swiss army knife for adding that certain digital crustiness to your pristine audio signal. It can simulate vintage samplers, classic video game systems, and other lo-fi paraphernalia. At extreme settings, it warps your audio with power you can’t get from a stomp box or full stack.

Features:

Zero-latency.

Sample rate reduction from 50 to 44,100 hz.

Bit depth range from 0.01 to 32 bit.

Parametric EQ on Input.

Parametric EQ on Output.

Drive adjustment for boost.

All values continuously variable, no large steps between values.

http://meatscience.net/

Better Run

Better Run is a free overdrive and saturation VST plugin developed by RunBeerRun. Compatible OS(s): Windows.

Better Run is a high gain overdrive plug-in for the electric guitar. It features 3 gain modes and an optional midrange boosting circuit.

https://runbeerrun.blogspot.com/

Best served cold

Best served cold is a free overdrive and saturation VST plugin developed by RunBeerRun. Compatible OS(s): Windows.

Best served cold is an amplifier simulator for the bass guitar with a 3-stage preamp section. It is similar to hardware preamps that accentuate dynamics.

https://runbeerrun.blogspot.com/

Berrtill

Berrtill is a free overdrive and saturation VST plugin developed by Shuriken. Compatible OS(s): Windows, macOS.

Berrtill is a distortion-unit modelled on circuit bent hardware.

http://www.shuriken.se/

Baxxpander

Baxxpander is a free overdrive and saturation VST plugin developed by Elogoxa. Compatible OS(s): Windows.

A vintage style saturation/bass expander unit.

http://www.uv.es/~ruizcan/p_vst.htm

bassPath

bassPath is a free overdrive and saturation Audio Unit plugin developed by Loud Software. Compatible OS(s): macOS.

bassPath provides the most popular effects processing path for bass guitar or synth bass. It includes distortion/overdrive, limiter, speaker cabinet emulator, Three band variable EQ, Chorus, and Delay. Custom user settings are supported, along with four factory settings.

http://loudsoftware.com/

Bandisto

Bandisto is a free overdrive and saturation VST plugin developed by mda. Compatible OS(s): Windows, macOS.

Multi-band (3 band) distortion. Creates the sound of torn bass bins and other subtle effects.

http://www.mda-vst.com/

ATK SD1

ATK SD1 is a free saturation and overdrive VST, VST3, Audio Unit plugin developed by Matthieu Brucher. Compatible OS(s): Windows 64b, macOS.

ATK SD1 is an emulation of the Boss SD1 overdrive. It is built on top of the Audio ToolKit library, and implements the overdrive (oversampling x8) and the tone sections of the original pedal.

Contrary to usual distortions, the SD1 features an asymmetric overdrive section that adds even harmonics to the sound.

http://www.audio-tk.com/

Aradaz Amp (Crunch)

Aradaz Amp (Crunch) is a free overdrive and saturation VST plugin developed by Aradaz. Compatible OS(s): Windows.

Aradaz Amp (Crunch) is a “Real Time Crunch Sounds Virtual Guitar Amp”. It has three stages of EQ and two built-in cabinet simulators.

https://aradaz.blogspot.com/

Aradaz Amp 2 (White)

Aradaz Amp 2 (White) is a free overdrive and saturation VST plugin developed by Aradaz. Compatible OS(s): Windows.

Aradaz Amp 2 (White Version) is a virtual guitar amp.

Features:

Two channels of overdrive and distortion.

Modern tube amp style.

Three stages of EQ.

4 x 12 cabinet simulator.

44100 – 96000 Hz sample rate support.

64 bit internal processing.

and more…

https://aradaz.blogspot.com/