Next-generation immersive surround sound Dolby Atmos, Auro-3D, DTS:X sound effects features and advantages

Next-generation immersive surround sound Dolby Atmos, Auro-3D, DTS:X sound effects features and advantages

One of the characteristics of the new generation of immersive surround sound: it is no longer limited to a flat surface, but puts more emphasis on three-dimensional sound space

The last breakthrough development of home theater surround sound systems was when the 5.1 and 7.1 systems appeared, which gave us the concepts of center channel, surround channel and subwoofer when enjoying movies, and also allowed us to start You can feel an unprecedented sense of space and surroundings at home. However, these two surround sound layout methods are only limited to the plane. Many times, many sound effects in movies are not necessarily horizontal. There are also many vertical directions, such as the rise and fall of airplanes, the falling of cannonballs, the flight of birds, etc. In At this time, it is difficult to reflect the specific sound details and layer orientation.

As a result, different foreign institutions began to improve the original 5.1 and 7.1 systems. For example, setting the surround channels much higher than the human ear to obtain a better sense of spatial surround, and adding front high channels to highlight the The sound details in the front height direction are reproduced, and the front wide channel is used to expand the front sound field and increase the detail and layering of the sound. However, since the program source is always recorded using a 5.1 or 7.1 plane system, even if this method is used to enhance the spatial sense of the sound, it lacks realism, and the upper sound field only presents an unreal sense of envelopment. This further prompted major manufacturers to start developing three-dimensional surround sound recording methods.

Thus, Dolby Atmos, Auro-3D, and DTS:X appeared. These three sound effects, which consider the sense of three-dimensionality and space from the recording stage of the program source, really bring about a transformation of surround sound from a flat plane to a three-dimensional space. Whether it is a 2-layer system, such as Dolby Atmos, or a 3-layer system, such as Auro-3D, the importance of the upper sound field layout is particularly emphasized, as long as the program source is natively recorded by these sound encoding technologies. It can show the delicate and tense details of the upper sound field. Therefore, what these three surround sound effects bring is an immersive sound effect, and the advantage lies in the grasp of the details of the entire sound space.

The second characteristic of the new generation of immersive surround sound: it is no longer limited to sound channels, but also has the expression of sound objects.

In the past, when we talked about 5.1 or 7.1 systems, we were used to referring to them as 5.1-channel systems or 7.1-channel systems. But with this generation of surround sound systems, in addition to the concept of channels, the element of sound objects has also been introduced. In the early recording process, it is no longer based on channels, but through every object in the entire sound space. Make it. The biggest disadvantage of the traditional channel surround sound system is that if the program source is recorded using 5.1 channels, no matter how many speakers you set up in each channel, it will not increase the details and layers of the sound, but only increase the volume of the sound. cover area. Because the sound produced by these speakers is the same. Sound object-based DolbyAtmos and DTS:X are important surround sound coding technologies that are improved on the basis of the channel system. It can record the sound of an object at a certain point in the entire sound space, and record the metadata of important information such as the coordinate position, audio and video size, and displacement time of each sound effect. Therefore, unlike channel-based systems, adding speakers to the system can add more sound details, which is why Dolby Atmos systems in home standards can achieve up to 24.1.10 systems. Although the specific speaker layout specifications of DTS:X have not yet been officially released, it is believed that more speaker layout settings will be used to obtain better details and levels of the upper sound field.

The third characteristic of the new generation of immersive surround sound: the processing core lies in the surround sound processor and AV amplifier

I remember when Dolby TrueHD and DTS-HD Master Audio had just been recognized by domestic audio and video enthusiasts. At that time, there were no corresponding AV amplifiers or surround sound processors that could decode them. They were mainly converted through Blu-ray players. into a PCM signal and then output to the amplifier. It can be seen that for 5.1 or 7.1 systems, the V amplifier is not the center that its decoding and processing must rely on. The signal source device can also play such a role. Many high-end Blu-ray players are even equipped with 7.1 amplifiers on the back of the fuselage. Analog audio preamp output for the channel. But it is completely different for Dolby Atmos, Auro-3D and DTS:X. They need to rely on higher computing performance processors for decoding and rendering, especially Dolby Atmos and DTS: which are based on sound objects: X, the information of each sound object in the program source must be obtained and decoded through the operator in the AV amplifier, and distributed to the speakers at the corresponding positions to achieve a completely different listening experience from the channel sound effect. If you want To build a new surround sound system, it must be equipped with a surround sound processor or AV amplifier with corresponding decoding capabilities. In addition, it is important to note that Dolby Atmos sound effects can be packaged with Dolby TrueHD and Dolby Digital Plus, while Auro-3D is DTS-HD Master Audio, allowing Blu-ray discs to accommodate more audio tracks with different sound effects.

Dolby Atmos enabled speakers The principle of upper sound field reflection speakers

The fourth characteristic of the new generation of immersive surround sound: groundbreaking speaker design reforms provide support for more home environments

As soon as they see that these new surround sound effects emphasize three-dimensional stereo sound, many audio and video enthusiasts who already have 5.1 or 7.1 systems or plan to build new systems will have a headache when they think of installing speakers on the ceiling.

Yes, whether it is Dolby Atmos, Auro-3D, or the upcoming DTS:X, they all mention the installation of ceiling speakers in their speaker layout specifications or demonstration systems. However, all three have reservations about ceiling speakers. First of all, Dolby Atmos can create an upper sound field effect through a dedicated two-way speaker module or integrated speaker, although the sound coverage is narrow and the directivity is only narrow. A strong mid-range and high-pitched sound can be achieved, but it allows users to build an Atmos system with minimal changes to the original system or changes to the home decoration layout. Auro-3D means that a two-layer system can be built with a minimum of A layer of overhead ceiling must be added, and the most important point is that all audio tracks on Auro-3D Blu-ray discs at this stage are Auro 9.1 sound effects with a two-layer structure. Finally, for DTS:X that has not yet been implemented, we also believe that ceiling speakers do not necessarily have to be installed, and can also be implemented through other means.

The fifth characteristic of the new generation of immersive surround sound: more emphasis on EQ equalization processing and bass management

In the post-debugging process of current 5.1 or 7.1 systems, we rarely control the volume of low frequencies through EQ equalization adjustments or a dedicated bass management system. However, as the number of speakers in new immersive surround sound systems continues to increase, especially after the addition of ceiling speakers, it is necessary to more accurately obtain a more balanced tone and adjust the strength and dive of low frequencies by simply setting or super It is no longer enough to adjust the position of the subwoofer. In most cases, more professional means are needed to adjust it. This is why these top-end surround sound processors have audio adjustment menus that are comparable to professional models. It is for this reason that it is not easy to make accurate post-adjustments to these systems. Fortunately, many processors or AV amplifiers are equipped with relatively mature automatic room sound field calibration methods, but these functions are only coarse adjustments, and For detailed adjustments, it is best to seek help from professional audio adjusters.