1. Hanging "foreign" head selling dog meat, obviously a domestic audio brand, in order to sell the product "foreign price", boasting that it is an international brand. Demolition: In fact, more than 50% of the world's audio is made in China. Most famous brands are made in China. There are very few completely imported products. If so, the price will definitely be higher. Many, so choose a brand that has a certain international reputation and is also manufactured in China. 2. The promoters use the paper to block the sound guiding hole. When the speaker sounds, the paper will be broken, which shows that the sound effect is good. Demolition: As long as the exhaust of the sound has airflow, this does not indicate the sound quality. 3. Fiber optic automatic docking. When the consumer does not pay attention, the business card or the bank card is placed between the two optical fibers, which proves that the optical fiber of the power amplifier can be docked by itself, and the product is superior. Demolition: General power amplifiers can be satisfied, do not believe you try. 4. Will not "whistle". When the promoters demonstrate, deliberately turn the microphone down, or block it by hand, or adjust the delay, reverberation, the sound will not appear "howling". Demolition: In fact, as long as the audio delay is too large, the reverberation is too large, the microphone, the volume is too large, and the microphone is facing the sound, the sound will appear "howling". 5. In order to prove that the acoustic shock absorber is good and the performance is stable, some promoters put the coin vertically on the sound. As long as it does not fall, it means that the sound is good. Demolition: In fact, as long as the speaker board is slightly thick enough, it will not fall, and the last speaker will not fall. If you are confused when purchasing home theater and audio equipment, please pay attention to the official WeChat (micro signal: cnhifi) consultation of China Home Theater Network, we will answer them one by one. 72V Charger,Electric Bike Chargers,Smart Charger,72V Lithium Battery Charger HuiZhou Superpower Technology Co.,Ltd. , https://www.spchargers.com