Honestly, I don't think there is a way to directly connect a soundbar to the TV set itself. I have the exact same model, and while I expected it to have bad sound (because almost all current TV Sets have bad sound), I expected to have at LEAST an Optical Output for direct connection to a soundbar. When I called JVC Customer Service, they could not give me an answer for how to do this, and it bugged the crap out of me.
I also discovered that A/V does not work either. It works, but there's echoing.
The workaround that I have done (since I have multiple Sound Devices, ps4, Cable Box, etc) was that I used a Optical Audio Switch for my PS4 and Cable Box, and directly wired the Switch to the Soundbar.
I'll give you a link to my setup equipment:
Switch: http://www.amazon.com/Portta-TOSLINK-Digital-Optical-Switcher/dp/B00KDZEWWO/ref=sr_1_4?ie=UTF8&qid=1451267794&sr=8-4&keywords=Optical+Audio+Switch
Any Optical cords would work, but I used these since they're cheaper and 2 came in the package: http://www.amazon.com/2-Pack-BuyCheapCables-Toslink-Optical-Digital/dp/B00K6SUUUQ/ref=sr_1_3?ie=UTF8&qid=1451267899&sr=8-3&keywords=Optical+Audio+cable+2+pack
It's worth mentioning that if you have an HDMI Soundbar, that it's easier to setup with this TV than the optical method that I just gave you. If your soundbar only has AV ports, I'd recommend some sort of converter.
I hope this helps you!
I have tried several different combinations to connect a sound bar to my JVC LT-49EM75, and it does not work, but if I turn the tv off, and the blue ray is still on, the sound bar will work. The owners manual to the tv is vague at best, so I don't know what I am doing wrong!!!! HELP! Thanks

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