Oh, I didn't recognise the voice from LBFaD! But you're right, he's doing amazing work with Chi Cheng, I've thought that from the start. He really brings out a lot of character. TXN's visual acting paired with Wang Baoshun's voice is a killer combo. 

 MamaI:

Why do some people need voice actors and some do not?

They may have a good or suitable voice with good line delivery and a good standard Mandarin accent, and enough skill to be able to do dubbing work. Then (depending on scheduling) it may be easier to let them do their own voice dubbing. 

Why is so much dubbing necessary in China? The reason most serious fans of foreign productions prefer “subbing” to “dubbing” is, it’s more fulfilling to hear the emotional content of the actor’s voices without the distraction of sound not matching the mouth movements. In Chinese productions I notice we’re often getting bad subtitles plus dubbed voices, which is very frustrating. I was told dubbing is used in China  because few actors have good language skills, and there are so many different languages and dialects, they have no choice. Is that true? Coming from the Hollywood system, I know it’s sometimes necessary to dub voices. The example we often hear about is Arnold Schwarzenegger. He apparently never learned to be a skilled actor because, even if he had studied his craft, and spent years perfecting it, like most actors do, he would have been dubbed in many roles anyway due to his thick accent. However, nobody considered him a real “actor” and he never performed a role that required any serious acting ability. I want to like Chinese productions despite the difficulties of understanding poorly subbed plots, obvious propaganda aspects, intense censorship, limited intellectual freedom, and excessive governmental control. But, they lack things that sustain my long-term interest such as varied and unique plots, layered performances, and the adventure of breaking traditional rules in order to be relevant, emotionally honest, innovative, thought provoking, and original. 

 KJTBOY:

What ? That’s not Tian real voice ??  Why it was dubbed ???

I think it's generally pretty standard in Chinese dramas, although I remember hearing somewhere that it's becoming desirable to be able to at least dub yourself, but that requires some skill. Reasons for dubbing I've heard before are 1) standardization of the Mandarin accent, 2) they're often filmed in really echo-y noisy locations, so it makes it hard to record the voices, and 3) because dramas usually have to go through censorship review, it allows them to change the lines to meet censorship restrictions without having to reshoot scenes...there might be another reason in there, but those are the ones I'm coming up with right now.