surround sound or home theate system for hard of hearing?

Zvox is a good brand but they only make Sound-bars and are also limited to US distribution...if you want a bigger company take a look at Klipsch, they make some outstanding speakers are very efficient, so they will play loud with very little power, if Klipsch are too expensive BIC of America also makes a line of speakers that uses horns and are very efficient the BIC Acoustech line....

I'm not sure about zvoxaudio. It's not a brand I am familiar with or have heard in action. What I can say is that speaking as as someone who is also hard of hearing that most additional audio systems are far better than the speakers built in to TVs. I have a very good system at home, and I install this kind of gear for a living. Soundbars like the zvoxaudio kits are definitely a step in the right direction, but they have their limits too. The bigger the speaker drivers and the speaker box then generally the better the sound. Go have a listen to some gear and bear this in mind. Good luck