Don't be greedy and cheap when buying a Chinese learning machine. It mainly depends on whether there is copyright and the sound quality is good. Those who don't have copyright will probably download some information from the Internet and put it in. You might as well download it yourself with your mobile phone. Only the person who owns the copyright can guarantee the quality. A good stereo usually costs thousands, so a cheap Chinese learning machine will definitely have noise, which will affect children's hearing. 1 1 month 1 1 day bought one at tmall's flagship store in Er Shen. It feels quite reliable, and the sound quality is good. Children like to listen to it.