Freeware - Mayerism Guitar Amp VST Plugin

https://mayerism.timpelser.com/

Versatile and completely free plugin designed for people in search of the soulful tone of a modern blues icon.

Freeware - Nice Stomps! VST Plugin

https://giannichiarello.com/product/nice-stomps-plugins/

Effects powered by NAM

Freeware - S-Drive Bass OD VST Plugin

https://modernmusicsolutions.com/products/s-drive

The Most Popular Bass Overdrive In The World - Now Available In Your DAW for FREE!

Freeware - Venomode Mesa Lite VST Plugin

https://venomode.com/mesa-lite

Mesa Lite is a free soft clipper for controlling peaks and increasing loudness without pumping. Mesa Lite is a free soft clipper designed to increase loudness and control peaks. Soft clipping allows you to gently smooth peaks, creating extra headroom for your mix or master without pumping artefacts like with a limiter. Clipping is used not only to control peaks, but can add saturation for a warmer, more glued-together sound.

Freeware - Vain Audio Sentinel VST Plugin

https://vainaudio.com/product/sentinel/

Sentinel is a banded distortion engine built for precise harmonic distortion and violent transformation. Split away a static band or track MIDI messages for tuned destruction. Now available as VST3/CLAP for Windows and AU/VST3/CLAP for MacOS Ventura and above.

Freeware - Caelum Audio Tape Cassette 2 VST Plugin

https://www.caelumaudio.com/CaelumAudio/?Page=TapeCassette2

Tape Cassette 2 is an audio plugin that emulates the warmth, noise and character of old tape cassettes. Following up from our well received Tape Cassette 1, we've updated the plugin with a sleek interface and more changes under the hood too. Along with a brand new selectable Type 1 Cassette Impulse Response (IR), we've improved the saturation algorithm, wow & flutter engine and implemented real sampled tape noise, all which results in a wonderfully warm and more accurate vintage sound. In addition to this you now have two VU meters to monitor your audio as well as selectable oversampling. Now you can easily add that classic sound to an entire track or use it directly on individual channels for added movement, texture, and warmth. Alternatively you can take it further than the material limitations of tape and push the parameters into a far more experimental soundscape, as a sound design tool.

Also, Flux Mini 2 sidechain pumper.

Freeware - Variety of Sound TesslaPro Mk IV VST Plugin

 https://varietyofsound.wordpress.com/2024/03/01/tesslapro-mkiv-released/

Very nice saturation plugin.

Freeware - Chaos Audio Freebie Plugin Bundle

https://chaosaudio.com/collections/tone-shop/products/freebie-plugin-bundle

Guitar stompbox FX

Get seven plugins, including reverb, drive, delay, and EQ, for FREE. 

Apollo - Classic Tube Drive 

Starlight - Shimmer Reverb

Cassini - Harmonic Reverb 

Transit - Digital Delay 

Booster - Clean Boost 

Spectrometer - 6-Band Guitar EQ 

Spectrobass - 7-Band Bass EQ

Freeware - Sinus Labs Bandbreite Tape VST Plugin

https://www.sinuslabs.io/products/bandbreite

Add warm, analog character to your drums, basses, and 808s. From subtle warmth to slamming saturation, this free plugin delivers. 

 Features: Analog Character,  Tape Slam,  Flutter Effect,  Tube Saturation,  HOT Signal Mode,  *NEW Oversampling

Freeware - ToneLib TL TubeWarmth VST Plugin

https://tonelib.net/tl-tubewarmth.html

At the heart of this effect is the desire to achieve a tube sound, with all its inherent roughness and vividness, from a dry digital signal. TL TubeWarmth adds even-numbered harmonies to the input signal, which contributes to expanding the tone of the instrument, giving it new colors and depth. The gentle tube overdrive further reveals new edges to the sound, emphasizing the new texture of the tone.

Freeware - Cymatics Origin VST Plugin

https://cymatics.fm/collections/plugins/products/origin-vintage-plugin

Origin is a vintage/lofi plugin created to make your samples sound like they’re straight from an old tape machine. The main knob is a resampler/bitcrusher with two special filters to make your samples sound “underwater” (this effect can often be heard in Drake songs) The other four knobs are Tape Saturation, Noise, Movement, and Chorus. Using these 5 powerful controls you can instantly give your samples a vintage vibe.

Freeware - Igorski VST Plugins

https://www.igorski.nl/download

Interesting set of creative effects. 

Freeware - JP01 Fuzzed VST Plugin

https://github.com/JP01/Fuzzed

Fuzzed is an analogue modelling distortion plugin, using "state of the art" state-space modelling techniques to model the physical circuitry of the famous Jimi Hendrix guitar pedal and implement it as a VST plugin using the JUCE API. Rather than simply modelling the general behaviour of the pedal, this plugin uses the circuit schematic to construct a highly accurate simulation of the pedal's behaviour, with full parametric control. This is then implemented as a VST plugin for use in real time. Included are some analysis screenshots of the comparisons between the output of the system and the real pedal, which shows the behaviour of the VST to be highly comparable to the real thing. Use of Fuzzed as a return effect can add beautiful analogue distortion to your sounds without losing the original tonal content. This work is the result of continued development of a plugin created and submitted as part of an individual university project.

Freeware - Disburser VST Plugin

https://kwhaley5.gumroad.com/l/xnsqmy

Reverse engineered kilohearts disperser

Freeware - Modern Music Solutions S-Drive Bass OD VST Plugin

https://modernmusicsolutions.com/products/s-drive

The Most Popular Bass Overdrive In The World - Now Available In Your DAW for FREE! Get a great start to your bass tone in just a few clicks, and get back to what matters most: creating music.

Freeware - Eftilo Mogano Overdrive VST Plugin

https://eftilo.com/plugins/mogano/

Overdrive circuits typically soft-clip your sound by blending a hard-clipped and filtered version of your signal with the original one, resulting in a softer and less harsh distortion. This is usually achieved in the analog domain via a non-inverting operational amplifier with the hard clipping stage in its negative feedback loop. Mogano takes a different approach. Inspired by the Tone Control module in Scirocco, Mogano models parts of a voltage-controlled filter commonly found in music synthesizers and drives it very hard to make it distort. Since the saturation is dynamic and mitigated by a delay-free feedback loop, it allows for a soft-clipped but unfiltered tone, with no emphasis on any particular frequency range. This makes Mogano suitable not only for guitar sounds but also for other instruments like electric pianos, bass, synthesizers and drums. The one-knob operation makes it very easy and immediate to use. Just turn it clockwise for more overdrive.

Freeware - Tonelib TL Bassdrive VST Plugin

https://tonelib.net/freeware.html

Bassdrive, Noise Reducer, and Tube

Freeware - The Kiss of Shame Tape VST Plugin

https://github.com/hollance/TheKissOfShame

The Kiss of Shame, debuted at the Audio Engineering Society Convention 2014 in Los Angeles, was a pioneering DAW plugin that leveraged commercial UX/UI design principles to shape its magnetic tape + circuitry emulation algorithms. 

To differentiate itself in the competitive pro-audio plugin market, The Kiss of Shame introduced groundbreaking features including an interactive, multi-touch-ready GUI and analog tape degradation simulation for distinctive audio effects.

The Kiss of Shame was the worlds first (and perhaps only) tape / analog circuitry emulation plugin that realistically models the effects of magnetic particle instability, lubricant loss, substrate deformation, drift, scrape-flutter, print-through and reel expansion/contraction into a suite of FX processing tools for sound design and music production.

It was also the first to leverage machine learning to account for the vast nonlinearities inherent in magnetic tape and analog circuitry. Last but not least, it's the only analog tape emulation that has fully-interactive reels that support touch and can write flange automation on-the-fly akin to a real analog tape deck.

The Kiss of Shame was not completely finished and never saw a release. The source code was graciously donated to the open source community by its owner in 2024.

Freeware - Spectral Audio (legacy) VST Plugins

https://spectral-plugins.com/

3 free plugins: Lofi Cassette, multiband transient shaper, and multifx

Freeware - Gnarl Distortion VST Plugin

https://myroslavartiukh.gumroad.com/l/gnarl

Unique distortion plugin with a choice of distortion algorithms, filters for the dry and wet channels as well as a reverb effect.