The study of loudspeaker positions

 

In the market of consumer electronics for audio products, some designs focus on sound performance and others might focus on ID appearances and prices. A unique ID sometimes limits the position of the loudspeakers. How can we get a balance between the ID appearances and acceptable sound performance? It’s always a critical task for the designer. Using the FEA (Finite Element Analysis) tool to predict and analyze the influences of sound performance when the ID was initially locked down and the optimizing position of the loudspeaker can be chosen.

Here are three scenarios with different positions of loudspeakers inside a product.

Figure 1 shows the loudspeakers’ positions inside the product of scenario 01.

 

Figures 1, the positions of loudspeakers in scenario 01

 

The two loudspeakers inside the product are in parallel, the z-axis is expected toward the end-users. Figure 2 shows the simulation conditions and results of scenario 01.

 

Figures 2, the simulation conditions and results of scenario 01

 

The simulated and predicted SPL (Sound Pressure Level) and impedance curve of scenario 01 is shown in figure 3.

 

Figures 3, the simulated SPL and impedance curve of scenario 01.

 

Figure 4 shows the loudspeakers’ positions inside the product of scenario 02.

 

Figures 4, the positions of loudspeakers in scenario 02.

 

Figures 5 shows simulation conditions and results of scenario 02.

 

Figures 5, the simulation conditions and results of scenario 02.

 

The simulated and predicted SPL (Sound Pressure Level) and impedance curve of scenario 02 is shown in figure 6.

 

Figure 7 shows the loudspeakers’ positions inside the product of the scenario 03.

 

Figures 7, the positions of loudspeakers in scenario 03.

Figures 8 shows simulation conditions and results of scenario 03.

 

Figures 8, the simulation conditions and results of scenario 03.

 

The simulated and predicted SPL (Sound Pressure Level) and impedance curve of scenario 03 is shown in figure 9.

 

Figures 9, the simulated SPL and impedance curve of scenario 03.

 

Figure 10 shows the comparisons of SPLs and impedances for the three scenarios. The simulated results tell us that scenario 01 has the highest SPL.

 

Figures 9, the comparison of simulated SPL and impedance curve.

 

It’s easy to understand that there are no impacts on the impedance curves if the loudspeakers’ positions are different. But the SPL will be influenced by different sound fields and reflections. From analyzing the compared results, scenario 01 has the highest SPL from around 1.2 KHz to 10 KHz. This means that it’s the optimized position for the product if the loudness is an important requirement for designing purposes. Scenarios 02 and 03 have almost the same performance if the product’s applications don’t need to extend the high frequencies over 10KHz. Or the cancellations of sound fields at high frequencies are more serious in scenario 03.