So, I've been whining for quite a while about how my Shure SRH840 44ohm headphones sound like poop with when connected directly to Helix. As a matter of fact, they were so bad I hadn't tried them in a long time and they actually sound better now than I remember them.... Not sure if that's a function of the upgrades since I last tried to use them. But stuff like fuzz pedals still blow them out, make the tone seem to actually have dropouts. I did pick up a pair of Beyerdynamics HD770 Pro 250 oh