Due to the magnetic leakage of the power supply of the multimedia speaker, the effect of using the speaker shield is very obvious when conditions permit. It can block the magnetic leakage to the greatest extent. The shield can only be made of iron-type materials. We should try our best to choose a shield manufacturer with big brands and solid materials.
The main function of the speaker shield is to make a magnetic shield, and it is necessary to use a magnetic material to make the shield. The better material is Permalloy, but it is expensive. In order to realize economic value, iron speaker shields are generally used. There is a situation where the main speaker has a bit of electric current, but the sub-speaker does not. Remove the toroidal transformer on the back panel of the main speaker a little further, and there will be no electric current. Why is this so? The audio line is close to the toroidal transformer, and although the transformer leakage is very small, it will also affect the audio signal transmission, so the sound of current will be heard. Sometimes it is inconvenient to keep the audio cable away from the toroidal transformer and the power transformer is not convenient, so the power transformer will be covered with a speaker shield.
For toroidal power transformers used in speakers, generally for audio separation, it is best to install a shielding cover. The toroidal transformer of the power amplifier using the speaker shield has small magnetic leakage, which reduces the noise generated by the current for the power amplifier, and the sound quality is quite pure and noise-free. Here, the editor of Lida Seiko still recommends that the toroidal transformer for audio products is better to use a speaker shield.