T-RackS WHITE 2A LVL AMP (Download)
White 2A Tube Opto Compressor/Limiter

The White 2A Leveling Amplifier is based on a legendary vintage unit that is entirely tube-based. It’s a totally different device in terms of construction where all the compression magic happens inside an optically coupled element formed by a fluorescent panel   some photocells: the famed T4A element. There is no electronic circuitry involved with the compression itself. Its just a tube amp with photo-resistors lighted by a fluorescent panel driven by the output signal. At the time of this invention there were not many ways of making an audio compressor: only variable-mu   optical. Optical was the simplest one   if proper elements for both the light emitting panel   the photocells were matched magic happened.
Originally intended for use in broadcasting it immediately became a truly signature unit for music recording   mixing. It’s a must-have for both tracking   mixing vocals but it’s also tremendously effective on electric bass upright bass piano winds   many other tracks where you need a gentle compression with great warmth   consistency. This is one of the few units in the audio industry that nobody will allow to be substituted with anything else.