Speaker layout is exquisite: Discussion on principles and methods

There are different methods for the arrangement of speakers under different conditions and situations, and the principles that must be followed in order to get the ideal sound effect.

Direct placement full-range speaker placement principles

A direct-firing speaker is a speaker whose sound is radiated directly outwards. It mainly relies on the radiation characteristics of sound waves to make the speaker directly send sound energy to the space. The direct radiation speaker has a larger bass radiation angle than the treble radiation angle. If the speaker is placed directly on the ground, the bass is reflected on the ground and is transmitted to the listener. The direct sound emitted by the speaker travels a shorter distance than the reflection The distance traveled by the sound, the direct sound of the speaker's bass reaches the human ear in advance, and the reflected sound then reaches the human ear, and the phenomenon of "first come and then come" of the bass will appear, resulting in bass ghosting. Therefore, direct speakers should not be placed directly on the ground or located close to the corner of the wall. It is best to use a metal frame to place the speaker above 1000px, arrange it at a distance greater than 1000px from the side wall and more than 500px from the rear wall. When the speaker is far away from the reflection interface, the bass reflected sound will be significantly reduced. Or when the ground in front of the speaker is a strong reflective material (hard and smooth material, such as marble floor), if the speaker is placed directly on the ground, you can use a sound-absorbing carpet in front of the speaker to absorb the reflected sound of the bass, but the bass cannot be fully Absorption, there is also a small amount of reflection.

Airflow subwoofer placement principles

The airflow speaker is a speaker whose sound does not radiate directly outwards, generally a subwoofer. Modern airflow subwoofers adopt advanced aerodynamic principles, and use the large-scale diaphragm vibration that only the bass can produce to achieve strong airflow changes, and use this airflow change to enhance the propagation of bass.

The airflow subwoofer is relatively free in terms of layout and installation, that is, it can be hung on the air or placed directly on the ground. But the effect is generally better on the ground, because the airflow subwoofer adopts the method of airflow propagation, so its bass has a certain directivity. Even if there is sound radiation, the proportion of sound radiation is also very small, so it achieves The reflected sound content behind the reflective interface is also very small, and the bass reflection volume is moderate. The subwoofer is directly placed on the ground, which can fully play the role of the ground, which is equivalent to using the ground as an extension of the bass horn. Such a large bass horn makes the sound resistance of the lower limit frequency sound of the speaker more matched, and the bass sounds thicker and fuller .

The listening area should fully obtain the direct sound of the speaker

Direct sound is the sound from the speaker directly to the listener, without reflection through the wall, floor and top surface of the room, there is no sound defect caused by the sound reflection of the interior decoration materials, nor is it affected by the indoor acoustic environment The sound quality is guaranteed and the sound fidelity is high. An important principle in modern indoor acoustic design is to make full use of the direct sound from the speakers in the listening area, and try to control the reflected sound.

In the listening area, if the listener can see the whole of all the speakers, and is located in the area where all the speakers cross and radiate together, the speaker's direct sound can be obtained. In general, hanging speakers is the best way to get direct sound in the room, but sometimes the hanging speakers may be restricted due to the low floor space and limited space. If there are conditions, it is best to hang the speakers stand up. Many speakers have a horn pointing angle of less than 60 degrees, a large horizontal pointing angle, and a small vertical pointing angle. If the listening area is not within the horn pointing angle, the direct sound of the horn cannot be obtained, so when the speaker is placed horizontally The axis of the tweeter should be consistent with the level of the ear of the listener. When the speaker is suspended, the angle of inclination should be adjusted to avoid affecting the effect of high-pitched listening.

The speaker layout should be symmetrical to the central axis of the room

An important requirement of the acoustic characteristics of the hall is to create a uniform sound field, that is, the volume of each position in the sound field must not differ too much. If the sound field is not uniform, it will make the consistency of the volume and timbre of the listening area worse. Therefore, the requirements for the indoor acoustic environment are that the symmetry of the building must be consistent with the acoustic symmetry of the room, and the speakers should be placed symmetrically on the center axis of the room. Only by achieving the consistency of architectural symmetry and acoustic symmetry can an ideal, harmonious and symmetric sound field be provided for the interior.

The volume of the speaker box should match the volume of the room

When using speakers in the area to play, pay attention to whether the volume of the cabinet is suitable for the room volume (that is, the length of the room × width × height). If a large volume of speakers is installed in a very small room, it will not only visually There is a sense of disharmony, and it may cause some problems in terms of sound effects.

Therefore, it is best to use small cabinet speakers in small rooms, and large rooms can use large cabinet speakers or multiple speakers to form arrays. In small rooms, the potential of large volume speakers may not be fully realized, and sometimes the sound quality is not ideal.

Centralized placement

Centralized placement means that the speakers are placed symmetrically on the side of the performance area in the room. Since the speaker is located on the side of the performance area, the sound comes from the performance area, and the orientation of the sound is exactly the same as the orientation of the picture, so that the listening and visual unity can be achieved. Moreover, all the speakers face the audience area in the direction of the stage. There is no relative placement of the speakers, and there is less interference of sound between the speakers. But the disadvantage is that the sound field is uneven, the volume near the speaker is large, and the volume far from the speaker is low. And because the speaker is very close to the stage, the sound of the speaker is easily transmitted to the microphone to produce howling feedback.

Decentralized arrangement

The decentralized arrangement means that the speakers are set around the room. This scheme is suitable for large halls. The rear area is equipped with supplementary speakers and ceiling speakers to play. It's a little bit that the sound field is uniform, and the sound of the speakers is covered everywhere in the room, and there is no situation where the volume difference is too much everywhere. And less affected by the acoustic environment. The closer the speaker is to the listener, the greater the proportion of direct sound. There is a speaker at each position in the listening area that is closer to the audience and can obtain stronger direct sound. However, in this arrangement, the sound comes from all directions, and the audience does not feel that the sound is coming from the performance area, and the separation of vision and hearing occurs, resulting in inconsistent listening. In addition, the interference between speakers is relatively easy to occur, resulting in damage to the sound quality.

In addition to the two typical arrangements of centralized and decentralized, there are a variety of speaker arrangements, such as surround, SIS, and hybrid, all of which are based on centralized and decentralized arrangements. In the process of speaker layout, it must be combined with audition. During the audition process, the position and angle of the speaker must be adjusted continuously until the sound effect is satisfactory. The speaker layout is an important part in the adjustment of the sound system. If this part is handled properly, you will get a high-quality playback effect.