Shattered Glass Audio has released SGA1566, a free tube saturation plugins in VST/AU format for Windows and Mac users.
SGA1566 is based on a single channel vintage tube preamplifier. With new additions on the original project, such as adding tone controls and made it stereo, SGA1566 achieve the most authentic analog sound, the whole circuit is simulated in real time using the high performance circuit simulator.
However, this level of sound fidelity comes at a price of high CPU utilization. For cases where such a CPU hit is prohibitive, the developer have added a model that is significantly less CPU intensive but slightly less accurate than the circuit simulation.
You can use SGA1566 plugin to add warmth to a track, as a saturation compressor, or to add “dirt” with tube overdrive.
SGA1566 is available for free download in both 32-Bit and 64-Bit for Windows and MAC.
More Details: SGA1566
Also check: Best Free Saturation Plugins