Placed this unit between my keyboard rig mixer and my powered speakers. I have real nice synths and the mixer is top-shelf stuff, but I was never able to get that really nice "headphone" smooth sound out of my powered speakers with just the 3 band eq on the mixer channels. No matter how much I adjusted the mixer, the speakers were just too harsh in the upper mids and top end, especially at higher volumes. So I bought this dbx 1215 EQ. I run either the main or the Aux outs from my mixer into the EQ, and the output of the EQ into my speakers. What an absolutely tremendous difference. I now have complete control of how the speakers sound since, with this EQ, I was able to eliminate the unwanted frequencies from my speakers. This is just fantastic and I kick myself that I didn't do it years ago. Instead of spending tons of cash on new speakers, try this first. Besides, you'll always be able to use this EQ, no matter what speakers you own now or in the future. Very solidly built, quiet, pro feel to the sliders and lots of input/output options for connecting to your gear. I should have bought this a long time ago.