A single-chassis phonostage preamplifier, the XP-15 represents a sophistication and maturation of both thinking and component evolution. Each new design of that evolution has brought a steady improvement in measured metrics and flexibility -- greater accuracy in the RIAA curve, greater range of gain from 46db to 76db...and the list goes on. But more importantly the evolution has contributed to a more robust sonic image presented with improved resolution and additional sonic ease.