Comparison JBL Tune Flex vs JBL Wave Flex

Impedance refers to the headphone's nominal resistance to AC current, such as an audio signal.

Other things being equal, a higher impedance reduces distortion, but requires a more powerful amplifier — otherwise the headphones simply will not be able to produce sufficient volume. Thus, the choice of resistance depends primarily on which signal source you plan to connect the "ears". So, for a portable gadget (smartphone, pocket player), an indicator of 16 ohms or less is considered optimal, 17 – 32 ohms is not bad. Higher values — 33 – 64 ohms and 65 – 96 ohms — will require quite powerful amplifiers, like those used in computers and televisions. And models with a resistance of 96 – 250 ohms and above are designed mainly for Hi-End audio equipment and professional use; for such cases, detailed recommendations for selection can be found in special sources.

Rated headphone sensitivity. Technically, this is the volume at which they sound when a certain standard signal from the amplifier is connected to them. Thus, sensitivity is one of the parameters that determine the overall volume of the headphones: the higher it is, the louder the sound will be with the same input signal level and other things being equal. However, we must not forget that the volume level also depends on the resistance (impedance, see above); moreover, it is worth choosing “ears” for a specific device first by impedance, and only then by sensitivity. In this case, one parameter can be compensated for by another: for example, a model with high resistance and high sensitivity can work even on a relatively weak amplifier.

As for specific figures, headphones with indicators of 100 dB or less are designed mainly for use in a quiet environment (in some similar models, the sensitivity does not exceed 90 dB). For use on the street, in transport and other similar conditions, it is desirable to have more sensitive headphones — about 101 – 105 dB, or even 110 dB. And in some models, this figure can reach 116 – 120 dB. and even more.

It is also worth noting that this parameter is relevant only for a wired connection according to the analogue standard — for example, via a 3.5 mm mini-...jack. When using digital interfaces like USB and wireless channels like Bluetooth, the sound is processed in the built-in headphone converter, and if you plan to mainly use this kind of application, you can not pay much attention to sensitivity.

A system that reduces the influence of ambient noise on the audibility of sound through headphones. "Noise reduction" with the help of a separate microphone (or several micro) "listens" to external sounds and sends the same sounds to the headphones, but in antiphase. Due to this, the noise heard by the ears is attenuated almost to zero and the user can enjoy the sound of the headphones without interference even in a rather “loud” environment. For filtering in headphones, Active Noise Cancellation (ANC) and Environment Noise Cancellation (ENC) systems are used. The first suppresses all the noise around the listener, the second - reduces the noise level of the environment. Active noise cancellation affects the purity of the sound, but the noise from the outside spoils the picture when listening to audio tracks even more.

Also in the headphones there is an adaptive active noise reduction system Adaptive ANC, aimed at automatically adjusting the sound of the headphones depending on the level of ambient noise. In a noisy environment (for example, when traveling on the subway), the Adaptive ANC system enhances the work of “noise reduction”, in the absence of loud sounds from outside, it weakens the noise reduction.

The capacity of the battery installed in the headphones of the corresponding design (see "Power").

Theoretically, a higher capacity allows to achieve greater battery life, but in fact, the operating time also depends on the power consumption of the headphones — and it can be very different, depending on the characteristics and design features. So this parameter is secondary, and when choosing it is worth paying attention not so much to the battery capacity, but to the directly claimed operating time (see below).

The capacity of the battery installed in the case (case) for headphones.

This parameter is relevant only for true wireless models (see "Cable type"). Recall that these headphones are charged from a case, which is usually equipped with its own battery and actually works in standalone power bank mode. Knowing the capacity of the battery in the case and in the headphones, you can estimate how many charges of the “ears” will last for one charge of the case. However, it should be taken into account that in the process of charging the headphones, part of the energy is inevitably spent on third-party losses, and the effective capacity of the case turns out to be somewhere 1.6 times less than the claimed one. This is the starting point for calculations: for example, a 300 mAh case will actually be able to transfer 300 / 1.6 = 187 mAh of energy to the headphones, and 30 mAh “ears” from such a battery can be fully charged about 6 times (187 / 30 ≈ 6).

The maximum battery life of headphones on one full charge of the battery or replaceable batteries in talk mode. A long working time will be relevant for those who expect to regularly conduct long telephone conversations. Note that in talk mode, autonomy may be lower than when listening to music, since the use of microphones and clear voice transmission algorithms puts an additional burden on the hardware of the headphones.

How long does the active noise canceling headphones (see above) last on a single battery charge (or a set of batteries) when noise canceling is not used.

This function is quite “gluttonous” in terms of battery consumption, up to half of the total energy consumed by the headphones can go to its work. Thus, models with noise reduction can indicate both overall battery life (see "Operating time"), and battery life with the noise reduction turned off.

The headphones have special protection against moisture and dust; also, this clause may specify the level of such protection according to the IP standard.

Not all waterproof headphones allow complete immersion in water, but in this case this is usually not required — water protection is mainly intended for safe operation in the rain (or during sports activities when the user sweats a lot). But the specific degree of such protection in different models can vary markedly, and here it is most convenient to evaluate it by IP marking. This marking consists of the letters IP and two numbers; moisture resistance is described by the second, last digit, and in modern headphones you can find the following options:

— 2. Protection against vertical drops of water in the working position and when the device deviates up to 15 ° from this position. The minimum indicator that allows us to talk about resistance to rain (however, without strong winds).
— 3. Protection against splashes falling vertically or at an angle up to 60° from the vertical. Provides resistance to moderate rain and strong winds.
— 4. Splash proof from any direction. With such headphones, rain of medium intensity is not terrible, regardless of the strength of the wind.
— 5. Protected against water jets from any direction. Allows you to transfer already a combination of strong wind w...ith a downpour.
— 6. Protection against strong water jets. It is considered the minimum level that allows you to swim safely (with your head above the surface of the water) wearing headphones.
— 7. Possibility of short-term (less than half an hour) immersion under water to a shallow depth (less than 1 m); continuous operation in immersed mode is not expected. In such headphones, you can no longer only swim, but also dive under water to a shallow depth (plunge with your head), but they are not suitable for full-fledged diving.
— 8. The highest level of water protection actually found in modern headphones (although theoretically there is a higher level, level 9). Allows long-term (more than 30 minutes) immersion under water to a depth of 1 m or more, and even permanent work in a submerged position. And although the latter is not particularly relevant for headphones, however, this degree of protection makes it possible to swim and even dive safely. However, note that specific restrictions on use in such headphones may be different, they must be clarified according to the instructions.

As for protection against dust (it is indicated by the first digit in the IP marking), its level in modern “ears” is indicated mainly in cases where it corresponds to level 4 (protection against objects 1 mm thick or more), 5 (allowed a small amount of dust that does not affect the operation of the device) or 6 (complete protection against dust). Also note that this number can be replaced by the letter "X" — for example, IPX7; this means that no official dust certification has been carried out for this model. However, this resistance in many cases can be assessed by the degree of protection against moisture: for example, devices with a moisture resistance of 7 or 8, by definition, do not let water through — which means that they are also not afraid of dust.

The total weight of the headphones; for true wireless models (see "Cable Type"), the weight of each individual earbud is listed.

This parameter is directly related to the design (see above) and some features of the functionality. Thus, the mentioned true wireless devices are very light, their weight does not exceed 25 g. More traditional in-ears and in-ears can be noticeably heavier, up to 50g for in-ears and up to 100g for most in-ears. Overhead models, for the most part, are quite massive: among them there are many models weighing 200 – 250 g, 250 – 300 g and even more than 300 g. It should be noted that a significant weight for false ears is often not a disadvantage, but an advantage: it allows them to stay on the head more securely, creates an impression of solidity and reliability, and most often does not create significant inconvenience.