PEBCAK...
I still stand by the monitors comment, though
There's a REASON a $4000 arranger sounds better than a $400 one... same reason a $1500 monitor system sounds better than a $300 one!
One thing that worries me is the inclusion of these tremendously powerful EQ and compression tools that are included in modern arrangers, completely at the control of people that usually have next to no skill whatsoever at using them! Obviously, we can see here how capable they are of taking a perfectly good sound, and screwing it up into something almost unlistenable
This didn't used to be the case... manufacturers, once upon a time, sent out the arranger from the factory already adjusted to the best it could possibly be, with no controls at all, and if it sounded like poo, you knew for certain that it WAS your sound system screwing things up, and as soon as you got that right, the job was done!
So much for 'home keyboard' users! 'Home' stereos don't come with a multi-band compressor built in... You can ruin a perfectly good sound in a heartbeat by using one of those incorrectly...
Those are high end studio toys, and even there can quickly make a good sound go south...
I would favor a return to the factory adjusting arrangers to their best, and not letting all these amateur sound technicians screw them up afterwards...
Just buy a sound system that is balanced enough you don't NEED to adjust them any, and we wouldn't be having this problem!