Feature: 1. The isolator can eliminate noise such as current sound of common electric and common ground products. 2. Transformer isolation turns ratio is 600: 600, has lossless output, high sensitivity and high reducibility. 3. Standard 3.5mm input and output headphone jack, convenient connection and strong practicability. 4. Sensitivity is 10‑20DB higher than similar low‑end transformer, full tone and pure sound quality. 5. The audio isolator module is small and compact, suitable for small cars and other indoor devices. Specification: Item Type: Isolation Module Material: Resin Model: XH-M372 Input/Output: 3.5MM headphone jack Size: Approx. 53 x 32mm / 2.1 x 1.3in Here are Some Common Sense of Noise and Common Ground: Audio isolation transformer is a transformer used for audio signal transmission between systems or equipment, which can avoid some problems caused by cascading audio systems and realize the safe transmission of audio signals. What is a common ground? This product is an audio common ground isolator, which is effective for the noise caused by the common ground of the audio source and the receiving device. To put it simply, common ground means that the grounding points of two electrical appliances are not at the same point. Due to the difference in grounding resistance, noise is transmitted into the electrical equipment through the ground wire, causing interference. Because the grounding points of the two devices are different, common ground noise may be generated. In the car audio, there is a kind of audio interference, like a whistle sound, the frequency of this noise will change with the engine speed. Therefore, this product can only eliminate the noise and current noise caused by the common electric and common ground products, but cannot eliminate the noise caused by other reasons, so you need to personally confirm the source of the noise. Determine Whether the Noise is Caused by Common Ground: 1. Use headphones to connect with car MP3 and car navigation AUX (3.5mm interface). If there is no noise in the sound heard from the headphones at this time, you can confirm that the noise of the car equipment is caused by the common ground. 2. Use an audio cable to connect a battery-powered mobile phone or MP3 (note that the mobile phone and MP3 should not be connected to any power source in the car, such as a telephone), and the AUX of the center console of the car, and play the music of the mobile phone, so there is no noise at this time , It can be confirmed that the previous noise was caused by the common ground. 3. Computer, Power Amplifier, Audio, CD: Use passive headphones to plug in the computer to try to hear whether there is noise, use the mobile phone to plug in the power amplifier, audio to audition, if there is no noise in the separate audition, it is basically judged that it is caused by the common ground. 4. After starting the car, the installed power amplifier has current noise, and some models will also have the situation that the greater the throttle, the louder the current noise, this product can solve this problem. 5. There is current sound between the power amplifier and the speaker or audio, you can install this product between the power amplifier and the speaker. 6. When the laptop is connected to the projector and the power amplifier is connected to the power amplifier, there will be noise. You can connect the laptop to the adapter power supply or use the battery. At this time, the noise disappears when the power amplifier is unplugged, or the noise disappears when the projector is unplugged, then the headphone jack and the power amplifier of the computer can be used. Add a common ground isolator to eliminate noise. . Package List: 1 x Isolation Module