Not all wireless headphones are equally useful or a few words about the problem of codecs.

    Having bought wireless headphones for listening to music, many users note that the fidelity of reproduction in them is lower than in headphones, where sound is transmitted through the wire. Such cases are not always the result of audiophile placebo. Very often they are due to codecs that are used to transmit sound. The source of the problem can be both the headphones themselves and the smartphone used for sound reproduction.


    This post will contain answers to common questions related to the quality of audio transmission via bluetooth from a smartphone to wireless headphones, as well as some recommendations on choosing wireless headphones and smartphones using the APTX codec. I am sure that the material will be useful to anyone who is puzzled by the choice and use of wireless headphones. If this is your case - welcome under cat.

    Why aptx?


    We already had a detailed post about sound transmitting codecs working with a blue tooth. Everything that is written in this article can be compressed into 2 sentences:
    Today, for most users, the most important of the arts is the most preferred codec for bluetooth sound transmission is APTX . It is especially good when the algorithm is additionally applied, which reduces the maximum delay time of APTX Low Latency .
    I make such a conclusion on the grounds that APTX encodes audio with a sampling frequency of 44.1 kHz, 16 bits and a bit rate of up to 352 kbit / s. And this is enough for such faithfulness of reproduction, which the overwhelming majority of people will not subjectively distinguish from CDDA. Also a significant factor is that this codec is relatively widespread in modern smartphones, music players and wireless headphones.

    And here the reader who is attentive and knowledgeable about the topic may notice that devices with SBC support are much more common than APTX, and will be right. It’s right that any device that uses the good old A2DP profile (and that’s almost everything) will work with SBC. But as they say, there is a nuance.

    The fact is that SBC was created on the basis of the MPEG-1 Audio Layer II codec, better known as mp2, as early as the year 1993. And, quite naturally, SBC inherited a lot of flaws from this algorithm, such as noise from quantization errors and other compression artifacts that are well-known to the ear.

    This codec is capable of providing a maximum bitrate of 345 kbps for stereo, as recommended, and 512 kbps, according to the maximum parameters of the encoder. In the subjective assessment of sound transmission using SBC compression, the quality of SBC sound is considered by many as unsatisfactory.



    SBCs are characterized by delays ranging from 100 to 250 milliseconds, which, for example, does not happen when using APTX Low Latency.


    The abundance of devices from Apple guaranteed the popularity of another codec - AAC. It provides a bitrate of 264 kbps with a sampling rate of 44.1 kHz. Subjective sensations of the quality of sound transmitted using AAC, users describe as a cross between SBC and APTX or equate to the latter. The number of devices working with this codec is limited by the use of malic technology.


    You can also read about other codecs (APTX, LDAC, etc.) that work with highres formats in the already mentioned post . I will only note that devices with their use are relatively rare.

    Compatible or what is wrong with APTX?


    Among the variety of smartphones sold on the territory of our vast country, I was not able to count a couple of hundreds of models that support APTX, and most of them are not cheap devices. This is largely due to the position of Qualcomm Inc., which makes money by selling APTX licenses.

    Interestingly, APTX sometimes does not even fall into the functionality of popular bestsellers and some of the flagship devices. For some of them, where the codec can be supported at the chipset level (i.e., where Snapdragon 835, 845, 821, 820, 810, 805, 801, 800, 650, 615, 410 stand, and possibly some others) , they come up with various ways to restore the codec to work, by “interrogating” the smartphone.


    As a rule, interrogations of this kind are carried out through backup. The native version, for example, of the popular MIUI firmware, is being replaced by an unknown android, and there is also a hypothetical risk of “scorching”. I am silent about the fact that it slightly violates the license rights of Qualcomm Inc. Just in case, I leave a link to the guide on this firmware , which may not kill your phone (but this, of course, is not at all accurate).

    I emphasize that this kind of non-guaranteed methods work only in cases when there is no official support for the codec, but it can be maintained at the iron level.
    Anyone else who wants to appreciate the difference between SBC and APTX will have to purchase a phone that is at least hypothetically (that is, at the hardware level) capable of supporting the technology.

    I would highly recommend any device that officially supports the codec. Why publish a link to their full list . And this is by no means for the sake of the licensing rights of developers, but for the sake of users who risk a lot by installing the left-hand firmware. Moreover, there is a possibility that in modern devices with official support there will be a more perfect and modern APTX HD, which we wrote about in detail here .

    Headphones


    When choosing headphones with APTX (Low Latency, APTX HD), it should be borne in mind that the technology assumes more active power consumption than when using SBC. For this reason, it is also worth soberly estimating the battery life of the headphones, which manufacturers often indicate, taking into account the use of the basic SBC codec. The real time of working with APTX is usually 30% less. In this regard, it makes sense to buy headphones with a larger battery capacity.

    In addition, many note that the use of this technology reduces the range of the device to 10-15 meters with direct visibility. For some, this is critical, especially if you plan to go far enough away from the source. It is better to check this option before purchasing or to clarify this information with the sales assistant when buying online.

    Personal attachments - not advertising for the sake of


    Sometimes in the comments they write to me that after the specifics of the choice, it would be nice to share personal preferences and recommend something that in my opinion will suit the readers (hello, vconst ).


    In this case, I can safely recommend one of the cheapest positions in our catalog, among wireless headphones with APTX, i.e. MARSHALL Major II Bluetooth. They cost about 6 - 7 kilorubles (the actual price on the website, prices sometimes change), only the wireless version of the legendary KOSS Porta Pro (Wireless) is cheaper, but their bass content is an amateur.

    My choice is due to frequency response with irregularity + -1.5 dB, low SOI, below 0.7%, full-size closed acoustic design, high sensitivity 99 dB / W / m, relatively high resistance - 64 Ohms and battery life of about 25 hours. I was also pleased with the well-thought-out ergonomics and the ability to connect additional wired headphones (i.e., they are able to work as a BT receiver).

    Total


    With the advent of APTX, Low Latency, APTX HD, audio transmission via Bluetooth has ceased to be associated with the opportunity for people who are inexperienced and not demanding to sound. Today, it is these technologies that make it possible to obtain the faithfulness of reproduction, which was possible only with wired signal transmission, and killed one of the latest myths about “bad digital sound”.

    Unfortunately, there are still problems with support and compatibility, especially when it comes to low cost smartphones, as well as a relatively small number of devices (for example, we have a little more than 60 of them in the catalog). I sincerely hope that my material will help you with the choice. I would appreciate your opinion in the comments.

    Jeans
    In our catalog is presentedA wide range of wireless and other headphones .

    Some of the images and tables used in the material are borrowed from the following resources:
    www.xda-developers.com
    www.androidauthority.com
    w3bsit3-dns.com

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