The IK Multimedia Vintage Compressor: Vari-MU Compressor/Limiter (Download) is a dynamic processor plug-in based on the classic Fairchild 670 Compressor/Limiter. This particular compressor is highly regarded in the history of mixing and mastering for its musical character. The software emulation is the result of an extensive analysis of the original hardware, with every feature and function recreated in the software version.
The processor consists of two separate and independent limiters that can be operated in the standard left and right or vertical and lateral components of a stereo mix via a decoding Mid/Side matrix. It features very fast attack times that make it suitable for use as a peak limiter while also having a wide enough range of release times for extreme limiting applications without pumping.
The plug-in is primarily used on a stereo bus for mixing and mastering, but it can also be applied to drum submixes and vocals to add presence, tube-emulated harmonic timbres, and cohere individual tracks and the overall mix together.
The user interface for the software offers a switch for setting Left/Right, Lat/Vertical, or Linked operation with adjustable DC Thresholds for the Left-Lat and Right-Vert components. Each side features a knob for controlling the time constant, the input gain, and the threshold. A simulated vintage VU meter provides visual feedback with selectable views of In, Out, and GR. Reset and On/Off switches allow you to compare the effects of the processor, and an output knob allows you to control the overall output level of the processor.
The plug-in is fully compatible with native 32- and 64-bit applications on both Mac OS X (Universal Binary) and Windows (XP/Vista/7/8) computers. It supports VST, RTAS, AAX, and Audio Units plug-in formats. It can also be used with the T-RackS CS standalone application (sold separately).