I don't use my JBL system, precisely because the sound is not good enough. Here are two solutions I've used:
1)
Large soundbar connects via HDMI and Optical to our TV
2)
Small soundbar connects via Optical to our TV
Both have really good bass and are bluebooth so they connect nicely to my phone. JBL makes a subwoofer that's a big box, over $300 - but I suspect it's only for the AURA model, that's what comes in the Pinaccle. Basically most any soundbar would be a huge improvement. Buy an affordable one, try it out and if it's not what you like, simply return it in the original packages for a refund and try something else.