What are the best Chinese online TV channels with English subtitles for passive Mandarin learning. I find Chinese a rather musical language and would love to watch subbed TV (news, documentaries, culture etc) in Mandarin.
I have a few tips:
If you own your house (or are on good terms with your landlord), I would recommend having a C-Band satellite antenna installed. The satellite you connect to will depend on the part of the world you live in. In Australia I had a 1.8m dish installed, and I connect to ChinaSat 6-B. (The whole set up cost AUD$800) There are more than 60 free TV channels broadcast from that satellite (plus many radio stations).
Use shooter.cn to download subtitles. Wherever possible I watch English language media with Chinese subtitles from this site. It takes a bit of a knack to figure out which subtitles to download, there are a couple of different encoding systems and there are subtitles in simplified, traditional, and some with both English and Chinese. A lot of the time the subtitles are targeted at a specific torrent (i.e. the .sub file from this site has the same name as the most-seeded torrent)
Find a Chinese / Taiwanese music charts website. Copy the titles into YouTube, and start making a compilation of tracks that you like. I listen to my playlist often in the car, It is amazing how after a few repetitions of the same tracks, you start singing along with the chorus.
Save your local Chinese radio station as a preset on your car stereo. Most major cities will have a Chinese language radio station.
Subscribe to the Chinese language podcast of your country's national broadcaster. Most major national broadcasters have a Chinese language podcast (National Public Radio, Deutsche Welle, Radio Canada International, SBS Australia, The BBC, &c.)
Of all of these I really recommend getting the satellite antenna. It's definately worth the money.
While not exactly passive in the sense you might mean, I found comic books (manga, 漫畫) to be invaluable while learning chinese. The dialog is very colloquial and it's easier for me to learn new words when I have something written down I can look up in a dictionary.
If you are in Greater China, comic books are everywhere, and I remember, in Taiwan at least, they have these great little comic book shops where you can rent or read in the shop very cheaply. Getting hooked on a long running comic book series that you are buying can do some serious dammage to your wallet.