SUB BASS 808

This virtual bass module features 36 tuned 808 bass sounds created using analog synthesizers, digital sine waves, guitar amps and other fancy gear.

https://hexloops.com/xsub-plugin

ATKBassPreamp

ATKBassPreamp is a bass preamp plugin, modeling the inverter input stage of a Fender Bassman followed by its tone stack.

The plugin is built with Audio TooKit and JUCE.

http://blog.audio-tk.com/2017/05/23/announcement-atkbasspreamp-1-0-0/

Noizefield Kick Machine

Kick Machine, a kickdrum and bass generator for modern music styles.

http://www.noizefield.com/products/kick-machine-free

Devil Bass Module

Devil Soundz has announced the release of Devil Bass Module 2.5, a free VST instrument plugin for Windows for creating deep to high smooth and vibrant basses.

http://www.devilsoundz.net/

SH-it Bass is a sampled bass sound from the Roland SH-101synthesizer.

You can make your own sound by mixing between the main oscillator (osc 1+2 from the SH-101), the sub oscillator and the noise generator.

• Monophonic.
• 3 layers.
• 25 main osc samples.
• 25 sub osc samples.
• 5 round-robin noise samples.
• Modwheel controls the LFO.

http://www.vst4free.com/free_vst.php?plugin=SH-it_Bass&id=2430

Sanford rev + delay

Sanford Reverb was originally priced at $25 when it was first released back in March 2009. The plugin was updated to v2.0 in July that same year, with the price increased to $35 for the full version. The brand new v2.1 iteration of Sanford Reverb is completely free to download from the developer’s website and also compatible with 64-bit systems. This is the third Sanford Sound Design product that was re-released as freeware this year, following Sanford Delay and Bass Tightener.

The plugin is one of the most versatile freeware reverbs on today’s market, at least when it comes to 64-bit compatible products. Sanford Reverb offers ultra precise control over early reflections (three early reflection points per stereo channel with time, pan and level parameters), global pre-delay, time and damp controls, MIDI learn, modulation for emulating cavernous spaces and a pair of filters for tone control. The plugin also features freeze mode for creative sound design. Freeze is one of the most fun features you can find in a reverb effect, definitely worth experimenting with. It works great for enhancing the sound of soloed instruments, lush vocals, or even those huge EDM style build-ups.
The CPU usage is surprisingly low for a reverb plugin. During our test on a single core Intel processor in MuLab 6, the CPU hit never exceeded 3% for a single instance of Sanford Reverb. The plugin strikes a nice balance between a quality reverb sound and low resource consumption, which are the two main qualities of a good reverb effect for everyday use in mixing situations.

http://www.lesliesanford.com/vst/plugins/

Bitsonic TB-303

Bitsonic TB-303 is a poly/monophonic bass line synthesiser with a single digitally modelled analogue oscillator, filter and decay envelope.

 http://www.bitsonic.eu/tb303.html

T Rex Bass & Delay

Max Project has announced the release of T.Rex Bass and T.Rex Delay, free VST instrument and effect plugins for Windows.

T.Rex Bass is a bass synth with an arpeggiator, a step LFO, Delay, Reverb and EQ.

T.Rex Delay is a tempo synchronizable delay.

http://maxproject.wix.com/maxproject#!vsti/cvpn

TSE BOD

TSE BOD v2.1.0

The B.O.D is emulating a well known bass processing unit.
If you need a good bass-tone quick, try this one!

https://www.tseaudio.com/software/tseBOD

Venom VB-303

Venom VB-303, a brilliant free Roland TB-303 emulation
http://www.kvraudio.com/forum/viewtopic.php?t=380007