Comparison AKG K371 BT vs AKG K371

This parameter is indicated only for specialized models that are not related to “ears” for general use. Nowadays, in headphones you can find the following specialization options: gaming, for active sports, office, monitor(aka studio), for DJs, for children's, for sleep. Here is a more detailed description of these varieties:

- Gaming. Headphones designed primarily for use in games - primarily with PCs and laptops (a separate type is available for consoles, see below for details). Externally they stand out primarily due to their design - usually quite bright and aggressive. Most of these models have an overhead design, most often in a full-size “Over Ear” format (see “Design”) - this provides maximum immersion into the gaming. There are other design options, but noticeably less frequently. An almost mandatory part is a microphone - for voice communication in online games. In addition, most multi-channel models fall into this category (see “Sound”) - such sound is most important for games.

— For active sports. Headphones good for sports. Such devices must, firstly, have additional fixation in the ears or on the head so as not to change their position during active movements; secondly, do...n’t be afraid of sweat (and ideally, rain, snow and other precipitation). With rare exceptions, headphones for active sports do not have a wire that could create inconvenience when moving. Sports headphones include earbuds models, earbuds, and some on-ear headphones. They share key character traits - a secure fit and at least some degree of IP water resistance (see "Protection (IP) Level").

- Office. Office headphones are designed for consultants, support operators and other employees who constantly have to deal with voice communications over the phone or the Internet. Accordingly, one of the main features in such models is the presence of a microphone. Also among office headphones, models for one ear are very popular (see “Sound - mono”), which allow you to hear both the interlocutor on the line and the surrounding environment at the same time. Many “ears” for this purpose use a USB connection (see “Connection”) - in the expectation that inexpensive office computers may not have specialized audio outputs at all. In this case, a small control panel for working with IP telephony can be provided directly on the USB plug; it allows, in particular, to accept and reject calls. There are also wireless models (usually with a connection via a radio channel, less often via Bluetooth), as well as specialized solutions connected to telephone sets using specific connectors.

— Monitor (studio). Headphones designed for use in professional sound recording and when setting up audio equipment. They are made only wired. However, the key feature of such models is different: they have the most even frequency response, which gives almost the same sound volume in all frequency bands, and a wide operating range, often exceeding the limits of frequencies audible to humans. Thanks to this, headphones for this purpose are able to clearly identify all the flaws in the sound signal - including nuances that are not noticeable on traditional “ears”; Such capabilities are indispensable in professional work with sound. On the other hand, for the same reason, there is no point in using monitor models for everyday listening to music: they not only reveal various shortcomings of the recording, but also give the sound a specific coloring that is unusual and even unpleasant for the average user.

— For DJ. Headphones originally intended for use by professional DJs when mixing tracks. In many ways they are similar to the monitor ones described above - in particular, they have a very smooth frequency response, providing the most reliable sound, and a wide frequency range. In addition, DJ headphones are usually made in a closed acoustic design and generally have high quality sound insulation, which allows you to maintain good audibility even in quite noisy environments.

- For children's. They differ from “adult” models primarily in appearance - both in smaller sizes and (in most models) in their characteristic bright design. In addition, children's's hearing is more sensitive to loud sound, and too high a volume is extremely undesirable for a child (including for psychological reasons). In light of this, children's's headphones may have corresponding features - for example, slightly reduced sensitivity, which does not allow the sound to be “boosted” to a high level, or a volume limiter, which can only be controlled by an adult.

- For sleep. Miniature headphones of a special anatomical shape, which allows you to calmly fall asleep lying on your side without discomfort in the ear. To reduce ambient noise levels, they are usually designed with passive noise reduction. These headphones can be used both for listening to music and for broadcasting white noise, nature sounds or waves. Advanced models also monitor sleep quality, and the alarm function turns on a wake-up melody at the appointed time. Such headphones are often called electronic earplugs.

— Wired. Headphones connected to the signal source with a cable. Such a connection is highly reliable and noise immunity, gives a minimum of distortion; the headphones themselves turn out to be simple, relatively inexpensive, light, moreover, they do not require their own power supply and have an unlimited operating time. The main disadvantage of this option is the presence of a wire, which limits the range and can create various inconveniences.

— Wireless. Headphones using a Bluetooth, radio, or infrared connection. The most obvious advantage of such models is the absence of a wire, which makes them very convenient to use; and the range is usually at least a few metres. On the other hand, wireless models are noticeably more expensive than wired counterparts, they have a limited operating time and require periodic recharging, and it is more difficult to achieve high sound quality in such devices (there are special technologies like aptX, but they increase the cost even more). In addition, traditional wireless headphones are also heavier and bulkier than wired ones; these shortcomings are devoid of true wireless models, but they have their own nuances.

— Combined. Headphones that allow both of the above connection option...s. The most popular type of such "ears" are wireless models with a detachable cable(see the relevant paragraph); another option is wired headphones with a standard plug, equipped with an adapter for wireless connection. Anyway, having such a model, the user can choose the connection method at his discretion: for example, you can listen to music from a computer via a wire, and when you leave the house, connect your “ears” to your smartphone via Bluetooth. At the same time, the combined devices are not afraid of a dead battery: you can simply switch the “ears” to the cable and continue to use them. The main disadvantage of this type of headphones is the rather high cost.

The specific connection interface provided in the headphones. At the same time, some models may provide several options at once - these are either combined devices (see “Connection type”) or wired headphones equipped with additional adapters.

— micro-Jack (2.5 mm). A wired connector similar to the popular mini-Jack 3.5 mm (see below), but smaller in dimensions. Equipment with such a connection is rare - they are mostly miniature devices, where there is simply no room for a 3.5 mm connector. Accordingly, this interface has not become widespread among headphones: it is almost never found in its pure form; models with such a plug are usually supplemented with an adapter or cable for a mini-Jack.

— mini-Jack(3.5 mm). Perhaps the most popular modern type of audio connector; If a device claims to have a headphone output, most likely it is a 3.5 mm jack. Accordingly, most headphones with a wired connection use this type of connector. It is worth noting that headphones with a microphone designed for such a connection are equipped with a special plug for a combined headphone + microphone audio connector (similar connectors are popular in portable gadgets and laptops). But with a jack intended only for “ears” without a microphone, such a plug may not work correctly. An alternative could be headphones equipped with two separate mini-jack plugs; See below for more details on this option.

— mini-Jack (2 x 3.5 mm).... Models with two 3.5 mm mini-jack plugs. This option is guaranteed to mean that we are not talking about classic headphones, but about a headset with a microphone: one plug is used for headphones, the second for a microphone. Such models are convenient when used with equipment that has separate 3.5 mm jacks for “ears” and a microphone - for example, for a PC.

— Pentaconn (4.4 mm). It is a 5-pin balanced output. Pentaconn uses a larger plug compared to the mini-Jack; its size is 4.4 mm, which is stronger and more reliable than the 3.5 mm connection. Pentaconn's balanced connection makes it possible to work with high-power audio signals. Thanks to this connection, it is possible to transmit a signal over a fairly long distance. Accordingly, such a connector is relevant for headphones of the highest category.

— Jack (6.35 mm). The largest type of Jack-type audio connector found in modern technology. Outputs of this type are found mainly in stationary audio equipment - for portable devices they are too bulky, where it is easier to use a 3.5 mm mini-jack. At the same time, the 6.35 mm connector is considered a more suitable interface for professional and audiophile-grade equipment: it provides a more reliable connection, greater contact density and, accordingly, less likelihood of interference. Therefore, although relatively few headphones (mostly premium solutions) are equipped with their own Jack type connector, many models with a 3.5 mm mini-Jack plug are equipped with an adapter to 6.35 mm.

- XLR. A characteristic round connector with a locking lock and 3 contacts (there are other options for quantity). Typically, it is used to transmit an analog signal over a balanced connection. This connection provides high immunity to interference, typical for professional use; at the same time, the connector itself has quite large dimensions. In view of all this, the presence of XLR is relevant mainly for headphones designed for use with advanced stationary equipment.

— Bluetooth. The most popular wireless connection option in modern headphones. This is due to the fact that built-in Bluetooth modules are available in almost any modern smartphone, tablet or laptop, and appropriate adapters can be produced for devices without this module (for example, a PC). True, the sound quality with a traditional Bluetooth connection is relatively low, but to correct the situation, special technologies like aptX and aptxHD are increasingly being used (see “Codec support”).
It is also worth noting that Bluetooth modules can correspond to different versions (the latest for 2022 are Bluetooth 5.0, Bluetooth 5.1, Bluetooth 5.2, Bluetooth 5.3, Bluetooth 5.4). This point does not affect the sound quality, but it determines a number of additional nuances - communication range and reliability , the ability to work through walls and other obstacles, resistance to interference, etc. In modern “ears” you can find the following versions of Bluetooth:

• Bluetooth v 4.0. An update in which the capabilities of version 3.0 (classic + high-speed Bluetooth) were supplemented with a third format - Bluetooth LE (low energy consumption). This communication standard is intended mainly for transmitting small amounts of information - in particular, service data packets to maintain a connection. At the same time, the creators managed to combine economical energy consumption and a long communication range - it can reach 100 m. This has a positive effect on the stability of the connection.
• Bluetooth v4.1. Development and improvement of Bluetooth 4.0. If we talk specifically about headphones, the key innovation for them in this version is improved noise immunity when working near 4G (LTE) mobile communication devices (in earlier standards, Bluetooth and LTE signals could overlap, which led to failures). So, for use with a 4G smartphone, headphones with Bluetooth support of at least v 4.1 are definitely recommended.
• Bluetooth v4.2. Further, after 4.1, development of the Bluetooth standard, which mainly introduced a number of general improvements in reliability and noise immunity.
• Bluetooth v 5.0. Major Bluetooth update released in 2016. One of the most notable innovations was the introduction of two additional operating modes of Bluetooth LE: an increased speed mode (by reducing the range) and an extended range mode (by reducing the speed). In the case of headphones, the main significance of these innovations is to improve the overall reliability of the connection, increase its range and reduce the number of dropouts.
• Bluetooth v5.1. Update version v 5.0, in which, in addition to general improvements in the quality and reliability of communication, an interesting feature has appeared, such as determining the direction from which the Bluetooth signal is coming. Thanks to this, a smartphone or other gadget that supports this standard is able to determine the location of connected devices with an accuracy of a centimeter; This can be useful, for example, for finding headphones that have disappeared from sight but are still working.
• Bluetooth v5.2. The next update, after 5.1, is Bluetooth 5th generation. The main innovations in this version are a number of security improvements, additional optimization of power consumption in LE mode and a new audio signal format for synchronizing parallel playback on multiple devices.
• Bluetooth v5.3 was introduced at the dawn of 2022. Among the innovations in it, they accelerated the process of negotiating a communication channel between the controller and the device, implemented the function of quickly switching between the operating state in a low duty cycle and a high-speed mode, and improved the throughput and stability of the connection by reducing susceptibility to interference. When unexpected interference occurs in Low Energy mode, the procedure for selecting a communication channel to switch from now on has been accelerated.
• Bluetooth v5.4. introduced at the beginning of 2023, increased the range and speed of data exchange. Also in Bluetooth v 5.4, the energy-saving BLE mode has been improved. This version of the protocol uses new security features to protect data from unauthorized access, has increased connection reliability by selecting the best channel for communication, and prevents connection losses due to interference.

— Radio channel. Wireless connection via radio channel that does not use Bluetooth technology (see above). Such headphones are usually equipped with an adapter that connects to the signal source wired - for example, via USB or mini-Jack 3.5. This connection method is more universal than Bluetooth; it can be used even with devices that do not have wireless modules. In addition, the radio channel provides a long range (often up to several tens of meters), and the sound quality is quite high even without the use of special technologies. The disadvantage of this option is the presence of an adapter, which is not always appropriate: for example, it is more convenient to use Bluetooth headphones with a tablet or smartphone.

- IR channel. Another method of wireless connection, the peculiarity of which is that it does not use radio waves, but infrared radiation. Theoretically, the advantage of such a connection is its resistance to electromagnetic interference, the disadvantage is that it only works in line of sight. In practice, the situation is such that in most cases it is easier to use Bluetooth or a radio channel for a wireless connection. So this option is found exclusively in specialized devices for equipment equipped with their own IR outputs - in particular, among headphones for car monitors.

— USB A. Wired connection to a standard (full-dimensions) USB connector. This option is found exclusively among headphones designed for computers/laptops or gaming consoles. One of its advantages is that sound via USB is transmitted digitally and is processed not by the computer's audio card, but by the built-in headphone converter; such a converter often provides better sound quality than the mentioned audio card. In addition, multi-channel audio can be transmitted via a USB connection - this point will be especially appreciated by gamers. Another advantage is that when using USB headphones, specialized audio outputs remain free, and you can connect other equipment to them - for example, computer speakers or a vibration pad.

- USB C. A relatively new type of USB connector, used in both desktop computers and portable devices - as a successor to microUSB. It is not very different in dimensions, but has a more advanced design - in particular, it is made double-sided, which makes connection easier. Most often complemented by other connection options (they can be either wired or wireless).

- Lightning. A universal connector used in Apple portable devices - iPhone smartphones and iPad tablets - since 2012. Not used by other manufacturers. Accordingly, models with such an interface are designed specifically for Apple technology (primarily iPhone and iPod touch players). This type of connection is especially relevant given the fact that in the latest iPhones the manufacturer has completely abandoned a separate audio output, and the only option for connecting headphones is the Lightning port.

— Branded connector. A connection connector that does not belong to generally accepted standards and is used to a limited extent in equipment from one or several manufacturers. Such connectors are found mainly among headphones for mobile phones. However, due to general standardization, this option has practically disappeared from the scene. Theoretically, the branded connector is also the Lightning described above, but it is separated into a separate category due to the popularity of Apple technology.

The length of the cable supplied with the headphones with the appropriate connectivity.

The optimal cable length depends on the planned format of the "ears". So, for pocket gadgets, 1 metre or less is often enough, for a computer it is already desirable to have a wire for 1 – 2 m, and preferably 2 – 3 m. And models with a longer cable length — 3 – 5 m or even more — are mainly designed for specific tasks, such as connecting to a TV or using in recording studios.

Recall that in some models the cable is removable (see below) and can be replaced if necessary with a longer or shorter one. Also note that there are extension cables that allow you to increase the length of the main wire; such a cable may even be included in the delivery, this point (and the length of the additional cable) is usually specified in the notes.

The type of cable provided in the design or delivery of the headphones. Note that this parameter is relevant both for wired or combined models (see “Connection type”), and for some wireless models - in particular, earbuds and in-ear headphones without a mount, where a wire connects one earphone to another.

- Round. The classic round wire is straight, without braiding or other additional accessories. It is inexpensive and in most cases quite practical, which is why it is found in most modern headphones. The disadvantage is that if the thickness is small, the round wire is prone to tangling; therefore, this option is considered not very convenient for compact headphones, such as in-ear or in-ear (see “Design”), which often have to be carried in a pocket or bag.

- Flat. The main advantage of a flat cable is that it does not get tangled as much as a round cable, and if something happens it is much easier to untangle. This is especially important for earbuds and in-ear headphones, which are often rolled up for storage or transport. However, larger overhead models can also be equipped with a flat wire.

— Round, braided. A round wire with an outer braid, usually fabric. See above for details on round wire. And the presence of a braid gives such a cable a number of advantages over the classic one with “bare” insula...tion. Thus, the wire turns out to be more durable, reliable and resistant to kinks and pressure, tangles less, has a solid appearance, and in some models the braiding also provides shielding from external interference. The downside of these advantages is the increased price.

— Spiral. A round cable, coiled into a spring. The main advantages of a spiral wire are that it practically does not tangle and can significantly stretch relative to its original length. The latter is very convenient if, as you use your ears, you have to change the distance to the signal source. The disadvantages of spiral cable are bulkiness and relatively high cost. Therefore, it is often used in mid-range and top-end headphones (including professional models).

- Round, braided. A cable in the form of two wires twisted into a spiral. This option should not be confused with a spiral wire - in this case we are not talking about a spring. This cable is notable primarily for its unusual appearance; For greater originality, the wiring can be made in different colors. It is also somewhat more tangle-resistant than the classic round one, although a lot depends on the thickness. At the same time, individual wires can be noticeably thinner than a solid round wire, which somewhat reduces reliability.

The location of the microphone, which the headphones are equipped with (if available, of course).

— On the cable. A microphone installed on the headphone connection wire (or on the connection cable in non-TWS wireless headphones). Can be combined with volume control. This option allows you to separate the microphone and headphones, reducing the weight and dimensions of the "ears" themselves; on the other hand, the microphone when worn is often quite far from the face, which can be inconvenient. Therefore, this design is mainly used among earbuds and in-ear headphones, where the size of the "ears" is critical.

— Built into the body. A microphone located in the housing of one of the headphones. This arrangement is convenient because there are no extra protruding parts outside (as in headphones without a microphone), while the microphone is close to the face, and in some models it is also able to perceive sound according to the principle of bone conduction. However installation in close proximity to the speaker gives additional interference and may degrade the quality of voice transmission. However, these shortcomings are not critical: interference can be compensated, and the built-in headphone microphones, in fact, do not need perfect sound transmission accuracy. Therefore, this option is quite popular nowadays, and it is fo...und not only in miniature models, for which the absence of unnecessary details on the outside is important, but also in rather large overhead "ears".

— On the bow. A microphone mounted on a small boom that is attached to one of the headphones. The microphone on the bow is the most popular among overhead headphones: a large cup can be supplemented with a boom without sacrificing convenience, and the microphone itself is located far from the headphones, which has a positive effect on the purity of the sound. The boom often has a swivel or detachable mount, which allows you to remove the microphone from the face until it is needed (by lifting the boom vertically along the headband).

— Retractable on the bow. Headband microphone (see above) with a retractable design: the headband can be pulled out of the cup when needed and can be tucked back inside when not in use. These headphones are more compact and have a neater appearance than models with a headband on a swivel mount: in a hidden position, the microphone takes up almost no space outside. The retractable microphone design is especially popular in gaming models (see “Intended Use”): in single-player games where you do not need to communicate with comrades, the microphone can be folded compactly.

— Removable on the shackle. Headband microphone (see above), which can be completely detached from the headphones if desired. Such a design can be useful, for example, if the “ears” are used both as gaming and as “marching and musical”: in a multiplayer game, the microphone is indispensable, and for listening to music outside the home, it can be removed so as not to carry extra equipment (which besides, you can lose).

— At the receiver. A variant used in wireless headphones with a separate receiver. In terms of design and use, it is similar to the microphone on the cable described above: on the one hand, the headphones themselves can be very light and tiny, on the other hand, the microphone may not be located close enough to the face, and when talking it will have to be brought closer.

— In the mount. In this case, most often means a microphone mounted on a neck mount (see below). This option is found mainly among wireless headphones, which have a signal receiver in the same mount. Such a microphone is located close to the neck, which allows you to achieve good speech intelligibility and at the same time cut off extraneous sounds even without any special additional tricks.

— On the cable and in the case. Headphones equipped with two microphones — one in the case, the other on the cable. The features of these variants are described in detail above. Here we note that their combination is extremely rare, mainly among high-quality "ears" with a combined connection (see "Type of connection"). In such models, when working via a wireless channel, a microphone in the case is used, and when connecting a wire, a microphone on a cable is used, which is less susceptible to interference.

— On cable and removable. Another kind of headphones with two microphones, also quite rare. One microphone in such models is mounted on a cable, the second — on a detachable bow. See above for more on each of these options, and combining them allows you to tailor the headphones to the specific situation. For example, the bow is very convenient for voice communication at home or office computers, but on the street and in transport it is better to remove it and use the microphone on the cable.

— In the case and removable. A rather rare and non-standard option is the combination of a microphone in the case and a microphone on a detachable bow. See above for more details on each of these varieties, and their combination is used quite rarely — in separate premium gaming models with a combined connection. The main point in this case is that it is more convenient to use a removable microphone in one place, with a wired connection, and in the “mobile” wireless mode it is better to remove it and get by with the built-in microphone. However, such features are fundamental mainly for the most demanding users, so this option has not gained distribution.

The headphones have their own volume control. Such a regulator can be placed both on the wire and on one of the cups (the latter is typical for wireless models). Anyway, this function allows you to easily adjust the volume: for this you do not need to go into the computer settings, press the buttons on the player or smartphone, etc., just use the control at hand. On the other hand, additional equipment complicates and increases the cost of the design, and also increases the likelihood of distortion. In light of the latter, volume control is almost never found in professional headphones.

Codecs and additional audio processing technologies supported by Bluetooth headphones (see “Connection”). Initially, sound transmission via Bluetooth involves fairly strong signal compression; This is not critical when transmitting speech, but can greatly spoil the impression when listening to music. To eliminate this shortcoming, various technologies are used, in particular aptX, aptX HD, aptX Low Latency, aptX Adaptive, AAC, LDAC and LHDC. Of course, to use any of the technologies, it must be supported not only by the “ears”, but also by the Bluetooth device with which they are used. Here are the main features of each option:

- aptX. A Bluetooth codec designed to significantly improve the quality of audio transmitted over Bluetooth. According to the creators, it allows you to achieve quality comparable to Audio CD (16-bits/44.1kHz). The benefits of aptX are most noticeable when listening to high-quality content (such as lossless formats), but even on regular MP3 it can provide a noticeable sound improvement.

- aptX HD. Development and improvement of the original aptX, allowing for sound purity comparable to Hi-Res audio (24-bits/48kHz). As in the original, the benefits of aptX HD are noticeable mainly on high-quality...audio, although this codec will not be out of place for MP3.

- aptX Low Latency. A specific version of aptX described above, designed not so much to improve sound quality, but to reduce delays in signal transmission. Such delays inevitably occur when working via Bluetooth; They are not critical for listening to music, but when watching videos or playing games, there may be a noticeable desynchronization between the image and sound. The aptX LL codec eliminates this phenomenon, reducing latency to 32 ms - such a difference is imperceptible to human perception (although for serious tasks like studio audio work it is still too high). aptX LL support is found mainly in gaming headphones.

- aptX Adaptive. Further development of aptX; actually combines the capabilities of aptX HD and aptX Low Latency, but is not limited to this. One of the main features of this standard is the so-called adaptive bitrate: the codec automatically adjusts the actual data transfer rate based on the characteristics of the broadcast content (music, game audio, voice communications, etc.) and the congestion of the frequencies used. This, in particular, helps reduce energy consumption and increase communication reliability; and special algorithms allow you to broadcast sound quality comparable to aptX HD (24 bits/48 kHz), using several times less amount of transmitted data. And the minimum data transfer latency (at the aptX LL level) makes this codec excellent for games and movies.

- aptX Lossless. The next stage in the development of aptX technology, which involves transmitting CD-quality sound over a wireless Bluetooth network without loss or compression. Audio broadcasting with sampling parameters of 16 bits / 44.1 kHz is carried out with a bitrate of about 1.4 Mbit/s - this is about three times faster than it was in the aptX Adaptive edition (see above). Support for aptX Lossless began to be introduced at the end of 2021 as part of the Snapdragon Sound initiative from Qualcomm.

- A.A.C. A Bluetooth codec used primarily in portable Apple gadgets. In terms of capabilities, it is noticeably inferior to more advanced standards like aptX or LDAC: the sound quality when using AAC is comparable to an average MP3 file. However, for listening to the same MP3s, this is quite enough; the difference becomes noticeable only on more advanced formats. AAC hardware requirements are low, and its support in headphones is inexpensive.

— LDAC. Sony's proprietary Bluetooth codec. It surpasses even aptX HD in terms of bandwidth and potential sound quality, providing performance at the Hi-Res level of 24-bits/96kHz audio; there is even an opinion that this is the maximum quality that it makes sense to provide in wireless headphones - further improvement will simply be imperceptible to the human ear. On the other hand, supporting this standard is not cheap, and there are still quite a few gadgets with such support - these are, in particular, Sony smartphones, as well as mid- and high-end devices running Android 8.0 Oreo and later versions.

- LHDC. LHDC (Low latency High-Definition audio Codec) is a high-definition, low-latency codec developed by the Hi-Res Wireless Audio Alliance and Savitech. In the vast majority of cases, its support is implemented at the hardware level in Huawei and Xiaomi smartphones. The codec is also known as HWA (Hi-Res Wireless Audio). When using LHDC, signal transmission from the phone to the headphones is carried out with a bits rate of up to 900 kbps, a bits depth of up to 24 bits and a sampling frequency of up to 96 kHz. This ensures a stable and reliable communication with reduced latency. The codec is optimally suited for high-end wireless headphones and advanced digital audio formats.

The declared operating time of headphones with autonomous power supply (see above) when listening to music on a single battery charge or a set of batteries.

As a rule, the characteristics indicate a certain average operating time in music listening mode, for standard conditions; in practice, it will depend on the intensity of use, volume level and other operating parameters, and in models with replaceable batteries - also on the quality of specific batteries. However, based on the stated time, you can fairly reliably assess the autonomy of the selected headphones and compare them with other models. As for specific values, relatively “short-lived” devices have a battery life of up to 8 hours, a figure of 8 – 12 hours can be called quite good, 12 – 20 hours – very good, and in the most “long-lasting” headphones the operating time can exceed 20 hours.