The IK Multimedia T-Racks Single - Bus Compressor (Download) is a dynamic processor plug-in based on the mix bus VCA type compressors found on British large format mixing consoles from the 1980's. The algorithm is designed to emulate every feature of the original hardware including the detection circuit, compression curve, and soft knee behavior to coherently compress and adhere different tracks together in what is commonly referred to as the "glue effect".
The software model expands upon the original hardware with the addition of new features such as a "grit" button for increasing 2nd harmonic distortion to add character as well as a side-chain high pass filter to remove low frequencies from entering the detection circuit. The high pass filter can be engaged to prevent the compressor from "pumping" the track.
The user interface for the software offers virtual knobs for setting the compression ratio (1.5:1, 2:1, 4:1, 10:1), the attack time (0.1, 0.3, 1, 3, 10, 30 ms), the release time (0.1, 0.3, 0.6, 1.2 s, and auto), the hi pass frequency (off, 60, 150, 250, 500 Hz), the threshold (from -20 to +20 dB) and makeup gain (from -5 to +15 dB). The 1.5:1 ratio enables subtle compression. A virtual VU meter provides visual feedback over the processing and a compression IN button allows you to observe the effect of the process on the signal. The left and right sides can be linked for stereo compression. A mid side button enables mid-side compression wherein the mid channel is the mono sum of the sound stage and the side channel is the difference between the left and right channels. A reset switch can be used to restore the original settings.
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).