2.3 Optimizing leakages
The virtual reality once again takes people’s attention, and there comes more hot topics about Metaverse recently. Acoustic designs for a virtual reality device usually involve pressure or near field acoustics. Here is an example of near field to reveal how to extend the bass for such kind of small speaker via designing the proper leakages on its enclosure.
The speaker designed for a virtual reality device is originally a closed box with side-radiation architecture.
The distance for the simulated S.P.L. is a near field of 5 centimeters which is referred to the distance between the ear and sound radiating area of the speaker. The simulation results show the in-box resonant frequency is 425Hz.
The 3D drawing is modified to a relatively simple geometry for speeding up the calculations but keep the key points to make sure all results are valuable. There are 4 leaking areas to participate the experiments.
The leakage at No.2 can extend the Fc to 190Hz but the frequency response has serious cancellations to cause the S.P.L. decreased a lot.
To compare with 4 leaking areas, leakages at No.1 and 3 have better frequency responses and less cancellation.
If we go further to investigate the impact on the differently leaking areas at the same side. The simulation results tell there is not too much impact on the sound performance.
The bass is able to extend in near field conditions by designing the optimized leakages on the enclosure. And all experiments can be built by a Finite Element Analysis tool, Kingstate uses COMSOL Multiphysics to predict in advance and decide the best design before making a real sample. It’s obviously save times and costs.
Check next: 3.1 Receiving path Fr simulation