The warm in-ear monitoring sound of the IE 400 PRO, with its rich, palpable punch, is the right choice for professionals who want to take their familiar studio sound to the stage. Even at high sound pressure levels, the IE 400 PRO reproduces its warm tone free from artifacts and distortions. With the newly developed TrueResponse technology, the tiny 7 mm dynamic driver delivers immense resolution and prevents acoustic stress, even during prolonged use. Distortions, frequency overlaps, and resonance peaks that often occur are no longer an issue. The total harmonic distortion has been optimized to an unimaginable 0.08%. The miniature design also allows for an ultra-compact build that can be individually adjusted thanks to the included silicone and memory foam adapters. This in-ear monitor is easy to handle and offers brilliant sound reproduction. Built to ensure a secure and comfortable fit even under extreme conditions for hours on end.