The precision-manufactured aluminum housing of the IE 900 faithfully protects the dynamic TrueResponse transducers at the heart of Sennheiser’s innovative X3R technology.
Our goal was to achieve a transparent sound with no distracting peaks or troughs. One thing this requires is clear separation of lows and mids. To ensure accuracy across this critical frequency band we’ve employed what is known as an acoustic back volume. It’s a small chamber within a chamber we have tuned to manage the slope and amplitude of the bass lift. The way the back volume helps achieve such a clear and natural sound signature is by controlling the direction and overall volume of air as it moves through the transducer system. What you hear is a pleasantly disciplined bass and mid-range experience. Unpleasant resonances and listening fatigue vanish in this small space with a big effect.