LONDON'S SPEAKEASY club shares a bond with New York's Max's Kansas City in that they are both music business hangouts. But where the sickly red lighting of Max's appears conducive to nothing so much as watching and being watched, the grey darkness of the Speak is directed towards the protection of privacy. Every night, top British musicians, producers and writers go to the Speak. They wrap themselves in its shroud of anonymity and quietly eat filet mignon and drink deep red wine.