My assumption that people with small TVs use them for 1/ gaming or 2/ watching TV in bed has not made me envy the choices available at all.

My partner and I sit outside a lot, so I'd go to thinking that a small TV would be a good idea (might go big tv when we get a new house), I found a cheap $150 panasonic 24in with 6w RMS, thinking that should be enough. Sadly its not, although a little better projecting the sound forwards rather than down, and I am making a box to mount the TV in to make it easy to carry in and out.

My bad was not looking at sound options in depth. The TV only has optical out, or HDMI out, but blowed if I can find an option to fit small PC speakers, as they don't do optical or HDMI it seems, none I can find, or a couple I did find, had less Watts than the TV. 

Considered optical converter, but these are powered, and I am trying to limit the leads in the box, prefering at this stage to just have the TV, hence Chromecast is being powered off the USB, but even if I freed that up, I don't think TVs are capable of USB audio out either. Sound bar is the immediate go to, but again, this is a 24in I am mounting inside a 57cm wide wooden box, and the only mini soundbars I can find are either limiting on their sound output, need power, or don't have ARC or optical input.

Am I stuck here, or is there some other option I haven't considered? At my last house I did have a TV outside, well, it was a projector actually, as space and under cover and sound was not an issue, but our covered area is a bit tighter now, hence the next place a priority will be space to mount a TV and sound bar without size restrictions.