While most in-ear systems rely on multi-way solutions from hearing aids, the IE 40 Pro utilizes a next-generation dynamic driver. The frequency range does not need to be divided into sections but remains a harmonious whole. It sounds seamless, and its frequency spectrum is significantly expanded. There are no distortions because the specialized membrane, unlike the stiffer drive principle of multi-way drivers, flexibly vibrates even at the highest levels. This also eliminates phase issues and dissonances in the inner ear. The difference is already noticeable in the entry-level model. Big in sound, small in the ear: the advanced driver system delivers a noticeably broader sound range to the ears of musicians, sound engineers, and DJs. The result is flat, fits securely, and is lightweight even during long sessions. Without monitoring sound, there is no performance. Accordingly, the IE 40 Pro is constructed to be highly reliable.