Koss KSC 9 Specifications, Tests and Review

The Koss KSC 9 are wired headphones. In the case of studio and professional DJ headphones, a wired connection is a standard and a necessity. In this case, connecting via cable reduces audio transmission delays and prevents unwanted battery drain as it would be in case of wireless headphones. The same is de facto true for gaming headsets. In case of headphones for normal music listening, the cable is rather a relic, although it still has its fans. However, the wireless option is much more popular for everyday use in today’s world. The weight of the headphones is 33 g.

The sound quality can be affected by many factors. For many users the frequency range is a key feature of headphones. The wider the range, the more detail and nuance you will hear while listening. However, every individual perceives frequencies differently, so the frequency range of headphones varies according to individual needs. The average person perceives frequencies in the range of 16 to 20,000 Hz, so headphones with a frequency range of 20 to 20,000 Hz are most commonly available. If you are looking for headphones with a good bass performance, you should aim for lower range values (bass represents frequencies up to about 256 Hz), while high range values (frequencies roughly above 2,048 Hz) will be better for reproducing high tones. The frequency range of headphones Koss KSC 9 is 40 - 20000 Hz. The headphone's sensitivity determines how effectively they can receive a signal from a source. The higher the sensitivity of the headphones, the louder they can play at lower power consumption. However, at high volumes, power consumption increases, which can be a problem when listening to music from a cell phone. A sensitivity value of around 85 dB is suitable for quiet environments, while a value of around 90 dB allows for quality listening even in noisy environments. Headphones with a sensitivity value of 100 dB and above are suitable for extremely noisy environments such as concerts. Headphones Koss KSC 9 are designed with sensitivity about 102 dB/mW.

The device connected to the headphones also plays a role most times. The lower impedance value (approximately 100 to 150 Ohms) is suitable for playback from mobile phones, laptops or other portable players that do not have a powerful enough amplifier. The lower impedance will ensure that the required volume level is achieved with less power, thus extending the life of the player. However, at the same time, with lower impedance, there is more distortion of the sound. Headphones with a higher impedance of around 250 Ohms and above are then more suitable for playback from really powerful signal sources or using a headphone amplifier, otherwise the sound coming out of them might not be loud enough. At the same time, higher-impedance headphones will also ensure less distortion in the sound. In the case of these headphones, the impedance reaches the 32 Ohm value. Total Harmonic Distortion of these headphones is Audio Output | Total Harmonic Distortion. The value quoted by the manufacturer is usually the average distortion over all reproducible frequency bands. This is not a crucial parameter to decide on when making a decision, but on the other hand, keep in mind that higher harmonic distortion can negatively affect sound quality.