Abstract: The typical micro-transducer dedicated for mobile phones and headphones produces at high output in small back enclosure significant distortion in the acoustical output. These typical micro-transducers are designed for very high sensitivity and their mechanical suspension compliances are designed for worst case scenario, free air environment or a very large back enclosure (were the air stiffness from the back enclosure is much lower than the mechanical transducer suspension stiffness). This leads to poor low frequency response, high distortion, non-linear SPL characteristic and unnecessary high system resonance fre-quency when the transducer is placed in a small back enclosure.