The HD9999 headphones are built for powerful playing. They feel perfectly at home in music with a heavier beat – rock and metal, but also in electronic music with a strong bass base. They have a wide frequency response in the lower registers and use it in the best possible way – playing a varied bass with rich texture. Bass does not interfere with other band ranges – it appears as much and in such a range as it was intended by the producer of the song. The midrange is typical rock – with energy and burr, allowing for a good rendition of the spontaneity of songs. The whole is complemented by unobtrusive, but clearly marked treble.

From the construction side the headphones are a typical closed design. The set includes two types of pads with different heights. They allow to shape the amount and character of bass. The design of the headband allows it to automatically adapt to the size of your head. The headphones have a detachable cable. The set includes both a straight cable and a spring cable. The plug is of the converted type – the cable ends in a 3.5mm plug with the possibility of screwing an adapter to the 6.3mm size. The set also includes a rigid case for safe transport and storage of headphones.