The 840c doesn't smooth over anything, it's really good with transients, especially that initial attack. On drums for instance the initial hit just jumps out and smacks you. I'm still a little unsure of the decay though, at times I get the feeling it's not always holding onto notes as long as it should. 
 
I also get a feeling that output stage is holding back the player from being as good as it could be. I wonder how good it'd sound with a zapfilter or a transformer coupled output.