Howdy! I mentioned last week I'd drop a few thoughts comparing the Empress Bass Comp and the Omnicomp after I'd spent some time with the Omni. I've used the Empress since it was released, and now I have a good number of hours in my music room and a bar gig with the Omni.
For context, my purpose in using a compressor is to constrain the dynamics a bit, but not lose the feel of my touch on the strings in a live mix. (I play fingerstyle and slap.) I don't mind heavy compression in studio recording--if that's what the producer wants--but live I need to be able to accent particular notes to bring the phrasing of a line to life, and to be competitive with the other instruments' volume; I've been through a good number of compressors trying to find that sweet spot. I'm happy to report that both the Empress and the Omni get me there.
The Empress has some features the Omni doesn't, but that mattered less to me than I expected. I figured I might miss the detailed metering on the Empress, but in practice the blinking light on the Omni works fine for seeing how much compression I'm triggering. I never cared much about the external side chain input on the Empress, but the adjustable HPF in the internal side chain is a big deal. That's the magic feature that keeps low notes from squashing the signal. I guess Josh set the Omni's fixed HPF the way I like it, because it works just fine without being able to adjust it.
I didn't mind the Empress's choice of three ratios, but it is a plus that the Omni's is adjustable. The Empress has that "color" switch with associated EQs, but I left that off. I can see how that would appeal to some folks, but I didn't use it. I want the compressor to be transparent, and the color to come from elsewhere in the signal chain. My Mesa TT-800 will give me all the harmonic color I'd want.
And of course they both have controls for all the standard compression parameters. Me, I gotta have knobs for the attack and release times, to get to my happy place. And a blend knob for doing parallel compression. An interesting thing: I didn't need as much of the dry signal as with the Empress. I liked the Omni leaning toward more of the compressed signal.
Not meaning to lapse into wine-tasting language here, but I do like the sound of the Omni a bit better. Rounder, more natural...organic, smoother, sweeter? Especially on the string pops, and some in the lowest register. As much as I like the Empress (and I'm not going to sell it), for me the Omni takes it up another notch.