If you're looking for a very portable, battery powered solution that can get very loud and is relatively flat, the MiniRig is a good choice.
It's one of the better consumer level Bluetooth speakers with low latency via a wired input by design. Very long battery life. Very portable and robust. 40 watts.
Software/firmware is a bit wonky. Perhaps the latest MiniRig 4 has that all sorted
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For guitar, it's pretty good. Amazing sound when focused on a single spot (personal monitor). Can fill a room or use outdoors (even better with something behind it to reflect sound). There's an eq setting for LOUD.
To be clear this is a one driver solution (you can add more units and/or their sub) that won't pass deep analysis. Some say they perform as good or better than many small studio monitors at the sub $300-500 price point per pair.
It's not going to replace a CLR, PA, high end monitors, and other devices that are large, heavy, and more expensive ... but you may not need that in all situations. This fits in a gig bag, weighs less than some pedals, is a useful tool for casual situations.
YMMV.