Sorry, I'm not familiar with the Vox, I just went on your description.
A bit leftfield, but when I practice at home, I plug into the aux on my dab radio (Pure Oasis) The sound is not bad at all, it's obviously very portable (built in rechargeable battery too) can really take a knocking/getting wet, and is by no means loud, but certainly louder than unplugged, and possibly loud enough to accompany an acoustic guitar/vocals. Got mine for less than a hundred quid.