JBL Under Armour True Wireless Flash Specifications, Tests and Review

​​The JBL Under Armour True Wireless Flash are wireless headphones. The wireless connection allows absolute freedom of movement and with that increases the comfort of using the headphones. This feature is very popular, especially when using headphones every day. The limiting factor of wireless headphones is a certain delay in the sound transmission between the source and the headphones (almost indistinguishable for a normal user), as well as the need to charge them (in the case of wired headphones, the headphones are recharged by connecting the cable itself). The technology used for the sound transmission used by the headphones is Bluetooth 4.2.

The headphones are designed as in-ear. In-ear headphones are plugged directly into the ear and they normally offer complete or at least partial isolation from surrounding noise. The degree of isolation also depends on whether the headphones have an ambient noise isolation function. Their indisputable advantage is that they are more compact than over-the-head headphones. The weight of the headphones is 16 g.

The sound quality can be affected by many factors. When it comes to frequency range, the wider it is, the more detail you will hear when listening. However, the range a person can perceive is highly individual. The average person is able to perceive frequencies in the range of 16 to 20 000 Hz. So the most common frequency range you will see on the market is 20 to 20,000 Hz. Lower frequencies up to approximately 256 Hz are considered bass frequencies. Therefore, the lower the bottom value is, the better the headphones will reproduce bass. Conversely, values from approximately 2 048 Hz upwards are treble. That is why headphones with a high upper value will provide a much more accurate reproduction of high notes. JBL Under Armour True Wireless Flash offers a frequency range of 20 - 22000 Hz. The sensitivity parameter determines how sensitively the headphones can receive the signal from the source. The higher the sensitivity value, the louder the headphones will be able to play with less power consumption. In general, a higher listening volume also means a higher power load for the connected device. So if you're buying headphones to listen to music from your mobile phone, for example, this is relevant to think about as you don't want to drain your phone's battery too much. Lower values around 85 dB are more suitable for listening in more quiet environments (for example, at home or in the office). Medium values of around 90 dB can provide good listening quality in noisier environments (for example, on public transport or in cafés). Headphones with high sensitivity values of around 100 dB or more are designed for really noisy environments, such as concerts. The JBL Under Armour True Wireless Flash has 95 dB. Overall, these headphones can reproduce sound up to 113 dB. However, be careful. Repeatedly playing music continuously at really high volumes can damage your hearing.

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 14 Ohm value.

An important part of these headphones is the diaphragm, which, simply put, converts the electrical signal into a sound. The thin diaphragm that is around 6 mm thick can react quickly to changes in the audio signal and improves high-frequency listening. However, it is less sensitive to bass. The medium-thick diaphragm of around 10 mm provides a fairly balanced sound profile, allowing you to enjoy both bass and treble. A thicker diaphragm of around 20 mm cannot react so quickly to changes in the sound signal, thus impairing bass listening. However, it is more sensitive to higher frequencies. This model features the 5.8 mm.

The microphone sensitivity is -25 dBV/Pascal. A lower microphone sensitivity will generally ensure that even quieter sounds are caught. On the other hand, in noisier environments, distortion of the recording may occur. With a higher sensitivity, the microphone will not distort the recording even in noisy environments. On the other hand, the microphone will not pick up quieter sounds. So it depends on the environment and the purposes you plan to use the headphones for.

Demanding users and technology enthusiasts will appreciate an intelligent assistant with whom they can partially control connected devices. For example, they can adjust the volume or request information about messages or alerts.

These headphones have a battery capacity of 85 mAh. In terms of headphone battery life as a significant factor in the purchase decision, it depends on what you want to use the headphones for and potentially how often you will be able to recharge them. Headphones with up to a few hours of battery life are more suitable for home use as they will require more frequent charging. Headphones with a battery life of around 10 hours or more are already more suitable for commuting and shorter journeys. However, nowadays you can also find headphones on the market that have a battery life in the higher tens to hundreds of hours. In this case, you do not have to worry about your headphones simply running out of power on longer journeys, and you will not have to deal with constant recharging. The battery life of the JBL Under Armour True Wireless Flash reaches up to 5 hour(s).

Charging time is 2 hour(s).