someone who works for Buchla mentioned this article to another person who then posted the link to a modular synth group on the internet, and maybe the information would also be of interest here …
http://sound.whsites.net/articles/vca-techniques.html
actually on the topic of compression, i read somewhere that if compressing material in the digital domain with any degree of bass element within the soundstage, an attack time of 18 milliseconds should be as fast as the compression effect should come on; any more would cause digital distortion of the bass frequencies.