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Mono VariMu Compressor


The century-old triode vacuum tube continues to set an amazing standard of sound quality, demonstrating its continued relevance decades after being eclipsed by cheaper alternatives. The variable-mu compression amplifier, as a single-stage, transformer-coupled triode amplifier controlled by a powerful DC amplifier, survives as a gold standard compression tool for the recording studio. For reasons explained below, Electronaut set out to design a new variable-mu compressor with no regard for the specific character of other historical variable-mu compressors. Interest in the potential of the technique and circuit topology, coupled with the availability of superior components and precision manufacturing capabilities, demanded an attempt at producing a superior variable-mu compressor; a compressor whose capabilities were as good or better than the state of the art, and whose features provided improved usability and a more enjoyable experience. Extraordinary variable-mu compressors already exist, so any new design needs to clear a high bar. No obvious limitations can be allowed, and no inconveniences can be tolerated. This is not a trivial task, and upon investigation it became clear that there were many problems that would need to be addressed. A small collection of some of those problems and the solutions Electronaut worked out appears below, because their descriptions do a pretty good job conveying the merits of the M97 compressor.