Sony MDR NC31EM Specifications, Tests and Review

The Sony MDR NC31EM 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 headphones are designed as in-ear headphones, which are inserted inside the ear to provide more or less isolation from ambient noise. The level of isolation may vary depending on whether the ambient noise isolation feature is present or not. One of the main advantages of these headphones compared to over-the-head ones is their stackability and easy portability. The weight of the headphones is 21 g.

The sound quality can be affected by many factors. When it comes to frequency range, a wider range will allow more detail to be heard during your listening session. However, it is important to note that the ability to perceive frequencies varies from person to person. The average person is able to hear frequencies in the range of 16 to 20 000 Hz. That is why headphone manufacturers usually focus on the 20 to 20 000 Hz range. If the lower values are lower, headphones are better able to reproduce bass tones, as these represent frequencies up to approximately 256 Hz. Conversely, values from 2 048 Hz upwards are treble. Thus, headphones with a high upper limit will provide a much more accurate reproduction of high tones. Headphones Sony MDR NC31EM have a frequency range of 20 - 20000 Hz.

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 31 Ohm value.

The headphones are composed of many various components, one of the most important is the diaphragm. Diaphragm transforms the electrical signal into sound and therefore its quality affects the overall listening experience. There are three types of diaphragms: thin, medium-thick, and thicker. A thin 6 mm thick diaphragm responds quickly to high frequencies but less sensitively to bass. The medium-thick 10 mm diaphragm provides a balanced sound profile, allowing you to enjoy both bass and treble. The thicker 20 mm diaphragm is more sensitive to higher frequencies but has a poorer bass response. These headphones are equipped with the 13.5 mm.

For an even more undisturbed listening experience, the headphones have a special Active Noise Canceling feature.

The Sony MDR NC31EM has a microphone built directly on the cable.