APTX on the smartphone: enjoying the sound of Bluetooth. Support App in headphones - what is it? SBC - the most common Bluetooth codec

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APTX Bluetooth - what is it For technology? Its essence and the way of activation is what we want to introduce the reader today. APTX console to traditional bluetooth should be added for a long time, but to this day a few users know that it represents themselves. Actually it useful featurewhich is especially appreciated by music lovers. That's just the built-in codec support today is difficult to find even on flagship phones. Often you have to include it yourself.

APTX technology:

Today inaPTX technology Already there are serious shifts. After the codec is upgraded, the APTX HD version and the mass of other modifications appeared. Read more about technology on.

What is it?

If you say simply, APTX is a Bluetooth codec that improves the quality of the audio signal. If smartphone I.headphones with APTX We can hear the best sound as 16 bits / 44.1 kHz, and the compression level is 4: 1. With this Bluetooth codec gets the ability to transmit data at a speed of 352 kbps.

In practice, the APTX codec allows the smartphone or other device to broadcast the sound as approximate to the CD. The most important difference between the "close" CD quality from the present lies in the compression of all transmitted data. This is a characteristic feature of all Bluetooth codecs, is mandatory to eliminate delays when broadcasting and encoding sound.

Thus, the APTX adapter compresses the data at the preparation phase. A receiver (usually headphones are usually) during the playback of the composition return data to the initial state. This inevitably leads to a delay.

To reduce the gap between video and sound, modifying technology - APTX LL, abbreviation LL denotes a "short delay". It is reduced to 32 ms. From a technical point of view, this indicator is far from the ideal, but a person no longer notices the delay. Technology is often present in gaming headsetswhere the minimum delay enters the fore.

Differences APTX and APTX HD

There is a modification of the codec with the HD - APTX HD console. It is improved and is able to extract the best audio signal quality (24 bits / 48 kHz). It works with the same level of compression, but is distinguished by a larger transmission rate of 576 kbps.

In practice, it means thatsupport APTX technology Improves sound quality, and APTX HD makes it even better. A smaller delay and better quality are the main differences of the HD version from the usual. Format 24 bits / 48 kHz is a full-fledged HD sound, which is valued in a circle of music alphas. It is for him many and buy expensive headphones. It has a minimum number of background noise and perfectly audible all the details. Quality improvement occurs due to the use of a more "soft" compression regime that is less distorting sound.

How to find out if the device supports technology?

To date, not all smartphones support APTX. This technology developed by Qualcomm, respectively, is supported exclusively on equipment and in this manufacturer. The desired functionality has a processor for processing CSR8675 sounds with Bluetooth 5. They can be equipped with Xiaomi, Samsung, iPhone and a number of other smartphones.

How to determine APTX which smartphones supportAnd which - no:

Wherever we read about Bluetooth on the eyes besides the very name, all sorts of different incomprehensible diquses and letters are also constantly falling across. Today, "in fashion" - the designation of APTX HD, which has recently replaced the shorter APTX.

It is clear that the prefix HD denotes " High Definition. "But how high, and what does this APTX mean? And how is the APTX differ from the new APTX HD?

In general, let's be able to understand.

what is APTX?

aPTX is digital technology (It is the so-called Bluetooth codec), which allows you to transmit audio signal as 16 bits / 44.1 kHz at a compression level 4: 1 and data rates 352 kbps .

This is if short. Actually, all this is without much difficulty will find in any description of the APTX codec. And yet, for sure, it will be written that thanks to the APTX your smartphone, a laptop, AV-receiver by the Bluetooth channel sound can be transmitted "with quality close to CD". What sounds already much more inspiring than boring numbers specification.

In general, APTX technology is capable of providing a music sound quality close to CD and, as a rule, provides.

Another thing is that it is necessary to distinguish the "close" and "true" CD quality. And these two "qualities" differ with the level of compression (compression), which in APTX, as in any other Bluetooth codec, is used to reduce the inevitable delays. emerging when encoding and transmitted stereo sound. Simply put, APTX always compresses the signal before shipping, and the receiving device (headphones, an external speaker, etc.) during playback, this signal is unpacking. This requires time, otherwise there is no way.

When you listen to music, then any delays in the devices do not have the values, and you just do not notice them. Despite the transmission wireless audiothe signal even between your smartphone and delay headphones can be very significant. But when you watch the video, any delays are manifested almost immediately. The actors suddenly cease to "fall in lips to words", the sound of the strima clearly does not coincide with what is happening on the screen, etc. If you are watching Netflix or other streaming video services, then you are all familiar too.

Therefore, it is specifically for the transmission of sound in video (and for all other cases where the minimum delay is important) a special version of the codec has been developed - APTX LL, where it means Low Latency, i.e. "Short delay". APTX LL also provides that the most "close to CD" sound quality, but reduces the time required for transmission and unpacking data to 32 milliseconds. Technically, this is also a lot, but this delay of the user's brain no longer notices. Therefore, APTX LL is used in gamers headphones and headsets, in which the minimum delay is more important even than sound quality.

New Mobile Headset Sennheiser Momentum Free with support for the APTX Low Latency codec

Now you can summarize: with APTX Bluetooth headphones, headsets, external speakers and other devices sound better, plus to this APTX also works more efficiently than most other Bluetooth codecs, because APTX support is provided in almost every device that sends and / or receives an audio signal via Bluetooth Channel.

what is APTX HD?

aPTX HD is the same Bluetooth APTX codec, but improved and which allows you to transmit audio signal as 24 bits / 48 kHz at a compression level 4: 1 and data rates of 576 kbps.

Yes, diftsy again. But from anyway, not much and, as we see, they are a little others. It is not difficult to notice that APTX HD is able to provide a more high-quality sound and with a much higher speed (lesser delay). And files in the format 24 bits / 48 kHz is already a real HD-sound, which is so appreciated by the owners of expensive wired headphonesand in which very little background noise and clearly audible even the most smallest nuances of sound.

It is worth noting that some "musical" models of smartphones can be transferred (for example, LG V series), but only in wired mode, i.e. After 3.5 mm mini-jack for headphones, and the quality of 24 bits / 48 kHz for them is actually the limit.

However, there is a difference between wired 24 bps / 48 kHz and wireless (i.e. bluetooth) 24 bits / 48 kHz. And it consists - in the compression of the signal. From the usual APTX, the new APTX HD is characterized by a more efficient compression algorithm (in descriptions it is also called "soft"), but not flawless.

In the sense, any compression - it always adds extra noise and hissing to the signal. And you hear it, although you do not always understand what it is from where. By the way, rock guitarists often use the signal compression intentionally to give the sound of the guitar an additional "rudeness" and "fuzzy".

For the APTX HD codec, special, "soft" was developed, especially in order to minimize any "rudeness" and "fuzzy", but completely remove the extra noise resulting from the compression of the signal, from the audio stream, even APTX HD is not at least.

Second, as we have already noted, if APT X transmits with a speed of 352 kbps, then APTX HD audio transmission speed is increased to 576 kbps. And taking into account the fact that the more kilo-, mega-, etc. Bit a second is transmitted, the better, then a higher speed speed just allows APTX HD by a more "soft" compression algorithm.

TOTAL : It turns out that in comparison with simply APTX, the new APTX HD in wireless can transmit a higher quality sound with smaller delays and a more gentle compression, and thus, as if, closer brings us to the quality of the sound, which is reached only with wired transmission audio signal.

support APTX HD.

... - She, of course, in deficiency. Since APTX HD is also the development of Qualcomm (as well as ordinary APTX along with all its variations), then this codec is supported only by equipment and / or software solutions Qualcomm. A. this moment Time is still - only the CSR8675 audio processor with Bluetooth 5 and the active noise cancellation system via Bluetooth and the sound transmission technology Qualcomm TruWireless Stereo. But also backward compatibility, I mean APTX support, they also have provided.

The first smartphone, which implemented support for APTX HD, became G5 from LG, with the release of which the South Korean company actually gave the start and headed the process of promoting a new codec on the market mobile devices user class. With APTX HD also work LG V20, The LG G6 and LG V30. Following the LG, APTX HD and other brands were actively introduced. In particular, Sony ( smartphones XPERIA XZ1 and XZ1 Compact), OnePlus ( smartphones OnePlus. 3, 3T and 5), as well as Sharp, Luna, as well as a number chinese manufacturers Android smartphones.

LG G6 I. wireless Audio-Technica with support for the APTX HD codec

On the other hand, that is, from the side of the playback devices, APTX HD you can find in Sony, Audio-Technica, LG headphones and other less famous brands. The number of such devices will grow as manufacturers will produce new models. And they will be released, since APTX HD, as we have already found out, really allows you to improve sound quality. But how much, this in each individual case, the user must be determined independently.

In each of his headphones review, I write about the quality of sound and technical characteristicsah, which provides it. But not all readers understand what APTX HD headphones are. One is just aware that this magic set of letters promises good soundFor others it is Abrakadabra without meaning. So I want to tell not about specific model Today, but about the type of headphones with the APTX codec. What does he give for the buyer, and does it even give?

Support APTX in headphones, what is it?

APTX codec is used in wireless devices to ensure quick transmission of audio files via Bluetooth with maximum quality preservation. I will try to explain how it works.

The concept of bitrate is the amount of data that you pass per unit time.

This figure determines the quality of music. If values \u200b\u200breaches 1411 kbps, the track will correspond on the quality of the recording on the CD. This is the most complete and detailed sound. But the wireless data transmission has not yet gives such a bitrate without additional tools.

Therefore, for maximum saving information when transferring from a source device to wireless headphones, special technologies are used - codecs. They allow you to squeeze the sound, reduce the sampling frequency, and then restore it again.

Part of the codecs make it with losses, such a technology is called lossy. Thus are thrown by those sounds that will be considered less significant.

If the codec is able to ensure compression, and then recovery to the same sampling frequency, that is, to the initial quality of the sound, then it performs its work without loss, and call it lossless.

The first method allows to compress data, for example, with the support of MP3 128, 13 times, but the compression without loss is carried out only twice and no more.

Now we analyze the information received in relation to APTX HD:

The bitrate is allowed 576 kbps, in the usual APTX only 384 kbps.
Multiply this value by 2.
We get 1152 kbps and 768 kbps.
Compare with the bitrate you need to sound without loss - 1411 kbps.
We get that the usual APTX is only a little better than MP3 320 or AAC. But the headphones with APTX HD allow you to get almost the sound of CD with minimal loss.

I want to note that when compressed, the sounds that are really not distinguishable for hearing are discarded, therefore such a high bitrate with stretch can be considered Lossless.

Features of headphones with support for APTX

But there is a small "but" in the use of APTX HD headphones. If the data source is not equipped with such a technology, then no effect of good sound, do not have to have to talk, and the codec only will load your devices.

Therefore, the meaning in the acquisition of APTX HD headphones is only subject to the presence of similar technology in the smartphone. Otherwise, the codec is useless.

First you need to know if the phone or tablet supports technology. Such information is indicated in the specifications. And if the instruction is lost, then information can be found on the Internet. And then remains to activate the codec in the settings for the developer, I think you already do it already, and if not, then google to help you.

Advantages and disadvantages

Is it necessary in wireless headphones APTX HD is already a little clearer, but for clarity you need to evaluate the pros and cons of technology.

What is good in using codec? Plus, here only one is a high-quality sound that depends on how precisely the original information is transmitted. As we have already found out, the losses are minimal and allowed to evaluate almost all the nuances of the composition.

The main drawback is only a limited number of smartphones supports APTX HD, which means that they will not all be able to estimate the codec, even with the support of its wireless APTX HD headphones.

On the basis of Android 7.0 use APTX technology, in 8.0 already use HD modification.

Supported codec and in recent models from apple companies, as well as samsung. Using ATPX manufacturers of gadgets paid, they are obliged to give the license fee to the CSR / Qualcomm technology owner, so the codec support devices from large manufacturers above average cost. Also headphones from the budget category, such as JBL, the codec is not supported.

I want to advise when buying APTX HD headphones, pay attention not only to the support of certain codecs, but also to other important parameters:

Not only the codec used is affected by the sound and bit rate, but also the Bluetooth version is better not lower than 4.0, as well as the necessary profiles - A2DP and AVRCP.
Autonomy of wireless headphones is one of the main conditions for comfortable use. It is also important how quickly and conveniently get to recharge the device;
Sensitivity and resistance also affect the sound. The increased value of the first combination with a low second gives a loud sound with good bass and high frequencies, but there is a risk of unpleasant noise;
Uncomfortable APTX HD Headphones cannot be used for more than an hour, as a result, pain in the ears and a bad mood. Therefore, whatever brand has a thing, convenience from use is more important;
The purpose is indicated in the specifications. Headphones are sports, versatile, road, moisture-proof, etc. From this will depend on their functionality.

Separately, I want to say about additional features APTX HD headphones, which add amenities:

MultiPoint allows you to match several devices via Bluetooth. For example, 2 pairs of headphones to one smartphone or vice versa;
Voice Assistant Siri or Google allows you to control the device without any movements. Suffice to say: "Siri, Make Potiche" or "Ivan Ivanchu" call, and the program will fulfill everything;
Actions radius, that is, the distance between smart and APTX HD headphones for normal operation, most devices are within 10 meters. But there are record holders that do not lose the pairing and on a 30-meter distance;
Active noise reduction completely disables you from external sound accompaniment. In such headphones, even at a construction site or in the subway, you will not hear anything other than music;
The sound varies depending on the type of headphones - plugs, liners or overhead.

In fact, the types of wireless devices and the variety of their functional are amazed today. Choose headphones on the basis of their desires and cost. But the presence and support of ATPX HD headphones determines the sound quality, which is undoubtedly very important.

Best models

From the variety of wireless devices, I picked up short review 3 best headphones with ATPX HD support. Of course, everyone has their own favorites, and I wonder your opinion. Share in the comments, what "ears" impressed you with their characteristics, and most importantly, the quality of sound.

Audio Technica ATH SR5BT

Closed overhead APTX HD Headphones with combined type data transmission. You can use the sound plug or Bluetooth version 4.2. Charging is enough for 38 hours of work. Resistance in 45 ohms in the sensitivity of 103 dB / MW, give a clean sound with muffled bass. frequency range from 5 to 40,000 Hz. Available voice assistant, use as headset and pair pairing with other devices. There are such ATPX HD headphones about 8,000 rubles.

Excellent assembly quality;
Compactness;
The presence and wired compound;
Very large battery capacity;
Stylish appearance.

Not very convenient push button;
No active noise reduction;
The sound is not sufficiently loud and bass.

These headphones seemed to me specially due to the softer sound, do not always want low frequencies at the head of the orchestra. Vocals and HF prevailing here. And they are very well sitting on the head, do not fly, even if you move very much. Well, of course a chic battery reserve.

Sennheiser Momentum Free.

Intracinal APTX HD Headphones connected by a cord, the so-called collar. The connection is only wireless, Bluetooth version 4.2. The battery is designed for 6 hours of use. Charging from PC through the microUSB connector in 1.5 hours. Magnetic zip will help avoid device loss. When using ATPX and on the source, headphones can be used to listen to classical music. Separate instrumental shades have been developed in detail. Fans of techno and hip-hop will have to work with the equalizer to add bass. Control key button on the panel below the headset. Do not lag when watching videos, used as a headset. The price of a wireless device is about 8,500 rubles.

Good charge with compact size;
Weight of only 40 grams;
Reliable brand;
Detailed, high-quality sound, highlighted vocals;
The possibility of joint pairing, as well as fast reconnect;
Remembers up to 8 devices.

The control panel I. bluetooth module prevent the headphones when driving and pulling;
Sit loosely, when moving it is easy to fly;
Basi muffled;
Weak magnetic clasp.

The sound is really wonderful. Especially good headphones for watching video. But the design tumbled, so they are not suitable for an active lifestyle. Model of overhead type - Sennheiser Momentum Over Ear Wireless M2 Although it is twice as expensive, but the sound quality and convenience won.

HARMAN / KARDON SOHO WIRELESS

Closed overhead APTX HD headphones. The sensitivity of 100 dB and the resistance of 32 ohms give a balanced sound in all frequencies. Bluetooth 3.0 version. Sensory control. Manufacturer for some reason does not indicate autonomous time Works and battery capacity. On the personal experience, Charge is enough for about 10-12 hours. The sound quality is excellent, complete study of all nuances, excellent data transmission, both when listening to entries and in streaming playback. Suitable for games and video. Such headphones are not suiced, in the area of \u200b\u200b15 thousand rubles.

High-quality sound;
Magnificent design;
Made of leather and metal;
Work is available through the cable;
Compact dimensions;
Sensory control that can be blocked.

Fly when driving;
The sensor triggers with a delay in a couple of seconds;
High price;
A little loses the microphone.

When paired with devices, which also support APTX, give a very decent sound. But most importantly in these headphones - design. This is a truly stylish thing in which you feel a little richer.

conclusions

APTX HD Headphones is the future. Many large manufacturers have entered it into use as a mandatory functionality. It is important that the signal source not only supports technology, it is sometimes activated by manually. Otherwise, it is impossible to estimate the quality of the sound. The fact that the codec actually works, no doubt. And the HD prefix gives even greater opportunities.

Interesting observation! There is a Jabra ELIT 65T model. In the characteristics there is no data on the support of the ATPX codec or APTX HD, but these headphones are distinguished by excellent sound quality. Either the manufacturer decided not to advertise all the parameters, or uses other audio file transmission technology. But this means that the codec is not an absolute quality assurance.

Bluetooth is a wireless data transmission between two short distance devices. This is done by radio waves (WPAN).

Few know that the name of Bluetooth technology has happened on behalf of the Danish king Harald Snezinet (Harald Bluetooth I, 958 AD). It was he who reunited part of Norway and Denmark. And the Bluetooth symbol itself denotes the Scandinavian runes B and H.

So, for transmission of music through Bluetooth, 3 factors are needed:

Sampling frequency (kHz): The higher the sampling frequency, the cleaner can be transmitted (close to digital). Distortion in sound is reduced and the audible frequency range is expanding.

Sample depth (BIT): The greater the sampling depth, the higher the resolution of the music. The dynamics increases as the range increases between soft and loud sounds. Thus it is possible to obtain more thinner sound levels and tonal nuances.

Data transfer rate (Kbps): This is the connection speed with which in this case the musical sound data is transmitted from the device to headphones. This, however, is not quite so. If we talk more accurately, this value indicates the possible amount of the transmitted amount of data for a certain point in time. The higher the data transfer rate with Bluetooth headphones, the more data (at the same time) can be transmitted by the device. Thus, the audio sound is significantly improved.

What do APTX reductions, PPTX HD and LDAC reductions?

These reductions are designed to designate Bluetooth codecs and basically describe various data transmission parameters. They differ in the frequency of sampling, sampling depth and transmission rate. In devices on Android 8.0, supports these audio codecs, and you can enjoy best quality Sound.

aTPX. - this is the slowest option for wireless transmission music. This technology provides at a sampling frequency of 48 kHz and a sample depth 16 bits maximum transmission speed of 352 kilobit per second. Analog signal is read 48,000 times per second and saved with 16 bits. In principle, these are solid numbers. For comparison, the CD is read and saved with identical parameters. However, relatively slow transmission leads to almost 50% of the loss of sound quality. Thus, the sampling depth is only 8 bits, which is associated with the resolution of music.

ATPX HD. Also has a sampling frequency of 48 kHz, but the digital signal is saved with a 24 bits separation. Dynamic range increases, which leads to more high quality Sound. Using LPCM (linear pulse-code modulation) leads to data transmission without loss from analog to digital alarm. The sound is thus cleaner.

PCM. - This is a modulation method that converts an analog signal into digital. Analog sound waves of music recording coming to the CD.

Sony H. Ear in Wireless

To what extent the transfer rate is adapted in this codec simply for transmission better sound Headphones are not yet known.

Bluetooth Sony LDAC codec - The best and fastest of the three possibilities of wireless audio.

With a data transmission rate of less than 1 Mbps at a sampling frequency (96 kHz) and a depth of a 24 bit, almost quality CD is achieved.

Compatible Bluetooth headphones

The modern market offers both in-ear headphones and ordinary headphones, eg, Sony h. Ear Wireless MDREX750BT / B, LG TONE ACTIVE + or PSB M4U 8.. Full list Supporting Wireless Listening Music Headphones can be found on the APTX-HD website. Headphones Sony MDR-1000X And MDR-1ABT support LDAC.

Many people complain that when listening to music through headphones, the sound quality is very bad. The problem concerns not headphones, and not the phone, but the codec that is responsible for transmitting sound signals. In modern phone models, a new APT codec appeared, which is considered better than analogs.

Apt is a technology that allows you to get the most high-quality signal through Bluetooth headphones. The essence of the technology is that it squeezes the sounds in the transmission process of the bluetooth bandwidth.

When APT X support is needed in headphones

Modern manufacturers of tablets and smartphones make models in which there is no port for connecting headphones. Therefore, the lack of connector requires to look alternative methods Connecting headphones. It is then that you need a system for transmitting sound without wires.

The second reason is that in the headphones with wires the sound quality is slightly lower. This is due to the fact that in the A2DP technology it is limited to frequency transmission. Because of this, the sound of the file is distorted slightly. APT is capable of transmitting sound signals without any deviations. Thanks modern technology compression, through bluetooth is transmitted only qualitative sound. More and more people choose the APT, so it has become massive and common.

Apt has two varieties:

aPT slowly transmits sound signals without wires. Thanks to this technology, with a totality of sampling 16 bits and sampling in 48 kHz, 352 kbps transmission is provided. These numbers are considered the norm to obtain a high-quality signal. Frequently compared with CD, and has almost identical characteristics. But the APTX has one serious drawback - the transmission of signals is slow, therefore up to 50% of the quality is lost in its process. Therefore, the sampling depth is two times lower than the normal value.
APTX HD. Discretization frequency is the same, but the sampling depth is increased to 24 bits. This contributes to an increase in the transmission rate, as a result, the sound becomes better. And thanks to LPCM technology, data transmission is carried out practically without loss (the sound quality almost reaches digital).

Attention! Code varieties a large number of. They are selected depending on compatibility with the device and the technical characteristics of the latter.

Features and requirements

The most important requirements are independence from other programs and performance technology. The codec requires a large amount of energy to download and transmit signals. Also, the load on the device itself is very high. Outdated versions Smartphones will not be able to support the codec, so you have to use conventional drivers, but it will not be possible to evaluate the sound through the APT. At the same time, modern models are already able to support the codec.

The requirements associated with support for APT concern not only the smartphone itself, but also headphones.

To sound well passed through bluetooth, the following factors are taken into account:

Sampling. What it is higher, the less excess noise in the signal is transmitted (it is close to digital). The frequency range is higher, and distortion disappear. Measured in kHz.
Total sampling. Responsible for the resolution of the sound. The speaker may increase relative to the range of different signals. Allows you to transmit more sounds of different frequencies. Measured in bits.
How fast is the data transmitted. It is a connection speed, and processes and transmits audio signals. In addition, the parameter shows the size of the information that is transmitted as some time. The higher the speed, the more information Sends the device. This allows you to improve sound quality. Measured in kbps.

Benefits Support APT X in headphones

The codec is capable of compressing sound files With bitrate up to 352 kbps. And if you set the Qualcomm - APTX HD modification, the bitrade support is 576 kbps support.

In order to transmit signals to headphones, you use the seal of audio streams. The last requires good performance Headphones. Frequency varies from 10 to 22000 Hz. Therefore, the quality of the sound is almost identical to CD. But before the vinyl does not reach.