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 - e-instruments Desolate Guitars Fragment Kontakt Instrument

https://e-instruments.com/instruments/fragment/desolate-guitars-fragment/

Get the signature sound that has shaped decades of music, full of character and emotion - FREE. Desolate Guitars Fragment presents a carefully curated guitar tone, sourced from the acclaimed full Desolate Guitars instrument. Explore this inspiring instrument with its iconic guitar tone, two legendary amps, authentic spring reverb and versatile FX macro control.

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 - Physical Modeling Virtual Guitar Instrument VSTi Plugin

https://weonix.github.io/Physical-Guitar-ICMC-Demo/

International Computer Music Conference 2020 

Guitar Virtual Instrument using Physical Modelling Synthesis with Collision Simulation 

Department of Computer Science and Engineering The Chinese University of Hong Kong (CUHK)

Freeware - Somerville Sounds Assorted Instrument Plugins

https://somervillesounds.com/prototypes/

Soft Drums Lite

Dusty Felts Piano, 

Antiquarian Echoes Ambient Guitars,

The Meyer Choir

Rubber Bridge Plucks

Freeware - CutterMusic Revitar 2 VSTi Plugin

https://www.kvraudio.com/product/revitar-2-by-cuttermusic

Revitar 2 is a guitar synthesizer and can produce a wide variety of guitar sounds and playing styles. To achieve added realism and playing flexibility, Revitar employs unique guitar pick, string and body simulations. No samples are used in the entire process, so no two notes ever sound the same.

Freeware - PA FREE bx_megasingle VST Plugin

https://www.plugin-alliance.com/en/products/bx_megasingle.html

Faithful reproduction of a Mesa Boogie Single Rectifier guitar amp. Now Free.

Freeware - Sommerville Sounds Antiquarian Echoes VSTi Plugin

https://somervillesounds.com/product/the-antiquarian-echo/

Guitar Ambience Awesomeness

Freeware - Helmut Keller Audio VST Plugins

https://www.helmutkelleraudio.de/

All of the following projects are related to the electric guitar and digital signal processing in the audio frequency range: 

 Guitar amp plugin 

A/B Blender plugin 

360 ° Panner plugin 

Wah-wah effect plugin 

Paper on digital state variable filters 

A software tool for measuring the impedance and frequency response of pickups for the electric guitar All plugins and software solutions are ready to use on different operating systems and they are free of charge. The technical background of the plugins and measurement tools is expained in every detail in the accompanying papers.

Freeware - Audiority The Sword EQ Boost Pedal VST Plugin

https://www.audiority.com/shop/the-sword/

Based on the same EQ/BOOST section of our Solidus VS8100, The Sword is the ultimate clean booster you’ll ever need! Clean boosters are basically a combination of tone shaping and amplification. We provided you a 10 band equalizer followed by a transparent clean booster for endless tonal shaping possibilities.

This ONE Adam Jones (TOOL) Technique Makes Him GREAT - Sound Like Adam Jones/Sound Like TOOL

Bass Flatter Fretless Accessory

Freeware - MOD Audio Desktop VST Plugin

https://mod.audio/desktop/#download_app

Fully stocked open-source Guitar Amp Sim and Effects Suite!!

Freeware - Tonocracy Guitar Amp NAM Sim and Effects VST Plugin

https://tonocracy.com/

The ultimate and NOW FREE guitar tone and effects software from Atomic Amplifiers!

Loads NAM Profiles!

Freeware - Neural Amp Modeler ParametricOD VST Plugin

https://www.neuralampmodeler.com/post/the-first-publicly-available-parametric-neural-amp-model

ParametricOD, a plugin that uses NAM's parametric modeling capabilities to give you a model of my overdrive pedal that is accurate across the full range of the pedal's knobs and switches.

How to mix electric guitars

https://www.lewitt-audio.com/blog/how-to-mix-electric-guitars

Getting your guitars to sit right in the mix can be tricky. But it doesn't take much to get your guitars where you want. This blog will show you 5 easy tricks to make your guitars sound spectacular!

Freeware - Echo Sound Works Vinyl Guitar VSTi Plugin

https://www.echosoundworks.com/vinyl-guitar-2

A huge update to our free guitar plugin. We're excited to release Vinyl Guitar 2, a massive upgrade from our first plugin ever! We listened to your feedback from the first version and added tons of additional controls, like a round robin on/off toggle and unique pitch shifting effects. With 10 distinct sample sets and per-layer sculpting ability for each one, you can mix and match different layers for a truly unique base sound. Then you can further adjust the sound with 11 customizable effects, including Speaker and Background Noise effects that are perfect for Lofi productions. There are also 2 different Delay modes, Ping Pong and Stereo Delay, as well as 2 Reverb modules: a Plate Reverb and a True Stereo IR.

Freeware - Audio Assault Amp Locker VST Plugin

https://audioassault.mx/collections/plugins/products/amp-locker

Amp Locker comes with free gear to get you started The free Prestige Amp, a british hotrodded amp, 7 Pedals, 7 FX and 11 fully adjustable 3D Cabinets

Freeware - Fractal Audio Cab Lab 4 IR Mixer VST Plugin

https://www.fractalaudio.com/cab-lab-4/

For decades, guitarists and audio pros have carefully selected, positioned, and mixed microphones on guitar speakers in the pursuit of great tone. Now you can do the same, and it is easier than ever before. With Cab-Lab 4, you get a 4-channel IR mixer, plus tools to EQ, align, and more, so you can select, position, and mix mics while listening in real-time. Meanwhile, new DynaCab technology makes tone sculpting easier than ever, eliminating the need to sift through countless individual IRs. In fact, the DynaCab system in Cab-Lab 4 offers even more resolution and flexibility than our hardware products, with 360° of placement at variable distances, the possibility of additional microphone choices, and more. Best of all, Cab-Lab is now FREE!