The F9 utilizes a hybrid design in which each channel is composed of one dynamic and two balanced armature (BA) drivers. The 9.2mm dynamic driver is specifically tuned to produce bottomless lows while the two BA drivers precisely portray extended upper-mids and highs. The F9 utilizes the standard MMCX connector for its interchangeable cables, and comes standard with both 2.5mm balanced and 3.5mm single-ended cables. The 2.5mm balanced cable is made of silver-plated copper wire, which ensures a balanced sound signature and a high level of detail retrieval. Of course, due to its balanced nature, the left and right channel wires are separated so that there is significantly greater channel separation-leading to a richer, more detailed musical experience. The 3.5mm single-ended cable comes with a full set of in-line controls capable of playing/pausing songs, switching tracks, volume adjustment, and even calls with its high-quality microphone. This marks the F9 a perfect complement to enhance your experience with your portable audio player or cell phone. The F9’s stunning exterior was inspired by something familiar we are all accustomed to: water. The sleek lines recall the ripples that occur when drops of water fall into a lake, making the F9 both more human and familiar. The ripple-like lines on the F9 not only give it a unique touch, but also serve to ensure structural strength and maximize the amount of space internally for a more optimized design overall. Moreover, the inside layer of the F9’s shell is specially lined with plastic to both better secure the drivers and eliminate internal resonances. You would never imagine that such a grand sound could come from something as tiny as the F9. Due to the way we have cleverly packaged the naturally-detailed BA drivers and the traditionally vast-sounding dynamic driver, we have achieved a fully cohesive sound that you would normally not think is possible from a puny in-ear monitor. The F9 utilizes a dynamic driver made of PEK (polyether ketone) polymer nanocomposite, known for not only being tough but also being light. This allows the F9’s dynamic driver to be highly capable of producing quick, detailed, and extended bass. We achieved maximum performance from the F9’s drivers by looking to the laws and principles of physics and psychoacoustics when designing our product. By doing so, the drivers are able to work in perfect harmony to achieve a cohesive sound that is absolutely able to reproduce every part of the sound frequency spectrum – allowing for a frequency response from 15 Hz to 40 kHz. The F9 has been certified by the Japan Audio Society to be “Hi-Res Audio” capable. This means that the F9 is capable of a frequency response up to 40kHz, which can fully reproduce the audio and give you a natural and life-like listening experience that truly lets you listen to the music the way the artists wanted it to sound. The F9’s outer aluminum shell is meticulously crafted using CNC systems – impressive already, but it doesn’t stop there. The shells are then carefully hand-polished and matched, before going through sandblasting and anodization. This complex overall process ensures that the F9 has a masculine, robust shell that is yet encapsulated in a tender beauty. Besides the 2.5mm balanced and 3.5mm single-ended cables, the F9 comes with a whole host of other accessories all designed to tailor and safeguard your listening experience. For instance, the F9 comes with two different kinds of ear tips – one set optimized for bass while the other is designed for a more balanced presentation. Each type of ear tips comes in small, medium, and large sizes. The color of the ear tips is even matched to the color of your F9 unit! We give you control over your listening experience, so you can listen however you want, whenever you want. The F9 also comes with our popular waterproof carrying case, so you can be rest assured that your earphones will continue to function for years to come.