Freeware - Dawesome ZYKLOP Resynthesis VSTi Plugin

 https://www.dawesomemusic.com/plugins/zyklop/

Meet Zyklop, MYTH’s fun, free-spirited little sister. She’s got just one gorgeous Eye, but that’s all she needs to pull you in. Powered by the same Re-synthesis V2 engine that made MYTH irresistible, Zyklop is ready to take you on a sonic adventure full of fun, exploration, and creativity.

Freeware - Bipolar Audio BP-909 VSTi Plugin

 https://unableton.com/b/fX4PJ

Roland 909 plugin

Freeware - Fracture Sounds Blueprint Collection Kontakt Instrument Libraries

 https://fracturesounds.com/product-category/free/

A large and growing assortment of high quality Kontakt instruments.

Works with Kontakt Player.

Google Experiment - Instrument Playground

https://artsandculture.google.com/experiment/8QFo2oQr2uT3pg

Cool web app for AI instrument samples.

Freeware - RdPiano SA-synthesis digital piano VSTi Plugin

https://github.com/giulioz/rdpiano?tab=readme-ov-file

RdPiano accurately emulates SA-synthesis digital pianos, such as the Roland MKS-20, RD1000 and the Rhodes MK-80 electric piano. It simulates the CPU-B board reused in different models, emulating the CPU and the custom chips. The emulation of the custom chips is derived from silicon analysis. It also approximates the BBD chorus and tremolo effect, albeit less accurately than the digital emulation.

Freeware - New York S&S Model B Piano Kontakt Instrument

https://www.pianobook.co.uk/packs/the-experience-new-york-ss-model-b/

The Experience – New York S&S Model B 

Steinway's famous semi concert grand with Performance and VR/Ambisonic perspectives - now with sympathetic resonance modeling

Freeware - Impact Soundworks Tokyo Scoring Strings Free Kontakt Instrument

https://impactsoundworks.com/product/tokyo-scoring-strings-free/

This free version of our flagship orchestral strings library includes two instrument sections (Violins I and Cellos) with the signature legato and user-friendly workflow of the Tokyo Scoring Strings engine and the beautiful, agile performance of Japan’s top string ensemble, Koichiro Muroya Strings. 

Kontakt Player compatible, and utterly risk-free. See for yourself just how easy it can be to write beautiful, realistic string performances with Tokyo Scoring Strings!

Freeware - creatools KEYS VSTi Plugin

https://musictop69.wixsite.com/creatools/keys

Acoustic, electric, electronic and digital keyboard samplemaps packed in an instrument with enough tools to allow you to freely edit, combine, modulate and mix them in creative and original way. ​

 Designed to help you synthesize your own original authentic sounds, configure and control them easily with your MIDI controller,​ use compression, saturation and convolution resonance to shape them to your taste and needs. Add reverb and delay for more depth, and use global filter to cut or emphasize acoustic aspects of your sound

Freeware - Insanity Samples Bamboo Flute Kontakt Instrument Library

https://insanitysamples.com/products/bamboo-flute-expressive-world-flute

BAMBOO FLUTE - Expressive World Flute is a deeply characterful and performance led solo flute instrument, with an exotic and worldly vibe running through every note. A free instrument designed to offer an introduction to the Insanity Samples ecosystem, and how our libraries function. With all the bells and whistles found on our flagship libraries. From the powerful and unique ‘Overlay Threshold’ functionality, to beautiful adaptive true legatos. Whilst the core, expected articulations are of course on offer, it wouldn’t be an Insanity Samples creation without a series of extended and special performance techniques. From ornamental and turn phrasing, to flutter tonging and experimental overblowing techniques. This flute will inject deep character into your writing, and inspire your creativity right out of the box. 

 Important Note: BAMBOO FLUTE requires the FULL version of Kontakt 5/6/7 or above. Downloading this with only the free 'Kontakt Player' will limit its use to 15 minutes per load.

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 - Wave Alchemy Triaz Player VSTi Plugin

https://www.wavealchemy.co.uk/product/triaz-player/

Triaz Player is a 100% FREE plugin and sample player, based on our advanced drum production plugin, Triaz. Get access to 4,000 award-winning drum samples and 200 inspiring presets. Import Triaz Expansions, and tweak, effect, mix and master your beats to perfection. Export your beats with unrivalled flexibility. Drag and drop audio stems, full mixes, one-shots or MIDI directly into your DAW. Available now as a free native AU, VST3 and AAX plugin for macOS and Windows.

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 - Quilcom VST Plugins

https://flowstoners.com/quilcom

Way too much stuff to list. Instruments and effects. Quality may vary.

Freeware - Venus Theory auras:polyscape Synth Sampler Plugin

https://venustheory.gumroad.com/l/vtpolyscape

For Decent Sampler.

Dark, organic analog expressions. Introducing auras:polyscape, the first in a new series of free instrument releases exploring the deep and cinematic sounds of the Polybrute 12 sourced from my custom patches and recorded through analog tube preamps to capture the glorious and imperfect nature of analog synthesis all wrapped up for the free Decent Sampler platform. Featuring a brand-new UI design and editor, polyscape brings the expressive nature of these custom patches featuring 'motion recording' to life with new dynamics and expression controls (bound to CC1 and CC11, respectively) a re-designed velocity response mode toggle for more organic and realistic velocity performance, custom IR's captured directly from the Polybrute 12, and a hand selected A-B layer system that can be set or automated to explore the morphing and organic nature of each sound to bring every performance to life. 

Freeware - WOK Cromina String Machine VSTi Plugin

https://www.kvraudio.com/product/cromina-string-machine-by-wok

Cromina String Machine is a physical modeling recreation of the electronic strings sound of the '60s and '70s. Solina, Crumar and Logan were the names which made it possible for bands to bring a string orchestra on stage or into the studio - the sound of these electronic keyboards featured on many songs of this era. WOK says that the sound-wise peculiarities of the frequency divider circuit and the BBD modulation section can not be successfully recreated by sampling, so they developed a plug-in with the main emphasis on the reproduction of this typical influence on the sound. Though the drawback is a higher CPU load, it gives a much better reproduction of the original sound. Although this plug-in has its focus on the typical Solina sound (including a phaser and delay effect), it can produce a wide range of typical sounds by using the integrated equalizer, vibrato, envelope variations (including a piano envelope) and other tuning controls.

Freeware - Slapassound Rudy Ruler Lite VSTi Plugin

https://www.slapassound.com/rudy-ruler-lite

Sampled instrument made out of a ruler. Free version.

Freeware - Indiginus Real Rotor Organ Kontakt Instrument Library

https://www.indiginus.com/real-rotor-organ

We sampled the sound of a 1957 Hammond B3™ through a spinning Leslie™ speaker at chorale speed, using a single drawbar setting popular in Rock, Prog, and Jazz.

Full Kontakt required.

Freeware - Ink Harmonica Kontakt Instrument Library

https://ink-audio.com/collections/ink-matchbook/products/ink-harmonica

Ink Harmonica is a free harmonica chord library for Kontakt. It’s inspired by the sound of singer songwriters playing a harmonica in a neck holder. It’s messy, loose and human.

Full Kontakt required.

Freeware - TX16Wx Software Sampler VSTi Plugin

https://www.tx16wx.com/

TX16Wx Software Sampler is a plug-in for the creative musician, inspired and modeled after the best hardware samplers with all the ease and new exiting features of modern software.