There's a thread about a mod to the QSC K10 at the Fractal Audio forums that basically states that the driver is out of phase with the woofer, and that it sounds better if you invert the phase of the driver. It also points out that there's a low end emphasis on the K10 that can be circumvented by adding a low shelf at 700 Hz with Q of 0.7 and a -3dB cut. The thread can be found here: http://forum.fractalaudio.com/amps-cabs/37051-k10.html I've done the mod to my K10 (it's ridiculously easy) but haven't tested it extensively yet, more on this when I've played with it for a while. I've also added said EQ correction to one of my 11R patches and it does seem to help. Now, here's my question: is there any way I can add a 700 Hz -3dB Q=0.7 low shelf using a compact device like a pedal or something similar? I wouldn't like the correction I apply to my K10 to go to FOH as well you know? Any suggestions will be greatly appreciated.