Cable length
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.
Impedance
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.
Frequency range
The range of sound frequencies that headphones can reproduce.
The
wider this range, the more fully the headphones reproduce the spectrum of sound frequencies, the lower the likelihood that too low or too high frequencies will be inaccessible. However, there are some nuances to consider here. First of all, let us remind you that the perceptual range of the human ear is on average from 16 Hz to 22 kHz, and for the complete picture it is enough for headphones to cover this range. However, modern models can significantly exceed these boundaries: in many devices the lower threshold
does not exceed 15 Hz, or even
10 Hz, and the upper limit can reach
25 kHz,
30 kHz and even
more. Such wide ranges in themselves do not provide practical advantages, but they usually indicate a high class of headphones, and are sometimes given only for advertising purposes.
The second important point is that a wide frequency range in itself is not a guarantee of good sound: sound quality also depends on a number of parameters, primarily the amplitude-frequency response of the headphones.
Weight
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.
In box
Among the equipment, it is worth highlighting
silicone and
polyurethane tips, relevant for in-ear headphones,
additional fixation nozzles and behind-the-
ear arms for better attachment in the ear,
interchangeable ear pads,
additional cable,
dongle,
aircraft adapter,
case / case and
docking station. There are also other accessories. More details about them:
- Silicone tips. Replaceable silicone tips used in in-ear headphones. Usually, several nozzles of different sizes are supplied in the kit, which allows you to adjust the headphones to a specific user. The practical advantages of silicone are softness, durability, general convenience and at the same time low cost.
- Polyurethane nozzles. Replacement tips for in-ear headphones made of foamed polyurethane. This material is somewhat more expensive than silicone, it requires regular cleaning and has a shorter service life - including due to deformation as it wears. On the other hand, polyurethane is ideal in terms of acoustics; it is these tips that are considered the best choice for lovers of in-ear “ears” with high-quality sound.
- Ear hooks. Removable devic
...es designed to additionally secure each earpiece to the ear. Note that such devices should not be confused with behind-the-ear mounts (see above). The main difference is that the arms are used exclusively in some models of in-ear headphones and earbuds as an additional option. In other words, you can wear such headphones without a bow, while the behind-the-ear mount is usually made non-removable and, in principle, you can’t do without it.
— Nozzles of additional fixation. Auxiliary caps for a tighter fit of the in-ear headphones. They are used to provide better fixation of headphones during sports or provide additional volume to users with a large auricle.
- Replaceable ear pads. Comes with interchangeable ear tips. In general, the ear pads are the part with which the headphones come into contact with the listener's ears. In full-size and on-ear headphones, they are soft pads on the inside of the cups.
— Case (case) / cover. Covers are usually called soft rag bags, they protect the "ears" mainly from pollution and take up a minimum of space. Cases are made of hard materials, they are a little more bulky, but they protect well from shock, pressure and contact with sharp objects. In any case, the complete case or case is optimally suited for the headphones and is more convenient than an impromptu protective casing.
- Charging case. Case - a case made of hard material - simultaneously playing the role of a charger. This feature is very popular on true wireless models (see "Cable Type"). The charging case usually has its own battery and the headphones are already charged from this battery; this design provides additional convenience in several moments at once. Firstly, the case, in fact, also performs the function of a power bank - an autonomous power source; the capacity of such a “power bank” may be different, but it is usually enough for several full charges of the “ears” (for more details, see “Capacity of the case”). Secondly, the ability to charge the headphones directly in the case reduces the risk of losing them. Thirdly, the charging procedure itself is quite convenient - just connect the cable to the case.
- Dock station. Stationary stand with the possibility of placing headphones and contacts for charging them. Also, docking stations are often used to transfer the sound track to headphones - they are connected directly to the sound source via a wire, and the sound is transmitted to the ears wirelessly within a certain radius of action.
— Clip for carrying. A clip designed to fasten the wire to a pocket, collar, lapel of clothing, etc. It provides additional convenience: thanks to the clip, the wire does not hang out, the likelihood of touching it with careless movement or catching on the surrounding object is reduced.
- Additional cable. An additional cable provided in addition to the main one may have different features and specializations. So, complete cables can vary in length, connector type, wire type, additional equipment (microphone, volume control), etc. These details should be specified separately in each case. Here, we note that almost all headphones with this configuration have a detachable cable (it makes sense to supplement a non-detachable wire with an extension cable, and it is considered a separate accessory - see below).
- Extension. A type of additional cable designed solely to increase the overall length of the wire. Due to the extension cord, you can adjust the headphones to the specifics of the situation: for example, “build up” the cable if you need to switch from a laptop to a TV or a stationary audio system.
— Airplane adapter. Dedicated headphone adapter for use with modern airliner entertainment systems. In such systems, a special way of connecting headphones is used - through two 3.5 mm jacks (and we are talking about classic "ears", without a microphone). Models with a traditional single 3.5 mm plug can only be connected to this output through an adapter; such adapters may initially be included in the delivery.
- Windproof microphone. Devices in the form of a foam rubber or "shaggy" lining on the headphone microphone capsule. Cut off unnecessary ambient noise and minimize the effect of direct exposure to air currents on the microphone, which can cause interference in speech transmission.
— Dongle. The dongle is used to simplify the organization of connecting wireless headphones to other devices. In fact, this is a radio transmitter (less often a Bluetooth transmitter) that non-contactly broadcasts sound to headphones from a connected device.
This list is not exhaustive and may include other optional items.