I bought these for my keyboard setup, which is rock orientated, Hammond clone, prophet, moog, piano etc. and I am delighted by how good the ES503s sound – they have far exceeded my expectations. Being able to use in stereo and not just mono is a huge plus point (and not sure others around the same price offer this).
I normally practice in a home studio with Adam studio monitors and I expected to lose a lot of clarity and definition when switching to these relatively low cost PA speakers, but actually they sound very hi-fi like with a nice sweet top end and plenty bottom end, none of the harsh brittle sound that you would normally expect from cheap PA speakers, I am actually really surprised by sound quality for the price.
I’ve not gigged them but they seem to have easily more than enough power for what I need.
Out of the box they do sound quite bass-heavy, and the bass while powerful is very slightly wooly, but I’m pretty sure some messing about with EQ will improve that.
The only slight criticism is the controls on the back are quite awkward to get to, a phone app would have been great, but not such a big deal as it remembers your last settings and you can also save your settings.
Bluetooth works very well and is very well behaved (and because they sound quite hi-fi like I connect them to my laptop when watching vids or listening to music).
All in all I would highly recommend, they sound great, are very easy to use and are extremely well priced.