And yes, I've searched, and found plenty of opinions and some info, but not much for specifics. I have the chance to pick up a used Elf integrator (the 18 Hz one) plus a bunch of cabs. Read this site, and the Bag End site, but there's no actual manual that I can find, just specs. I know some people here have/have had them. I'm wondering if I could use it with the equipment I have or if I'd need to buy a slew of other equipment, which makes it less of a good deal. I've read how people have used them with Brand X preamp, into integrator, into power amps, into speakers. Great so far. I don't have any power amps, though I could maybe secure 1. Is it possible to adjust the signal strengths such that I could take the signal from my wireless (if it is powerful enough with its gain turned up) into the ELF, then run the split signals from the ELF into a solid state bass amp (Or the effects return thereof) for the lows, and into the front of my 400+ for the rest of the signal? I'm not going to ditch the 400+ to buy a preamp for the ELF, so I won't buy it if it can't work with a head. If it is possible to use it this way - I can get either the s18e or the d12e. The d12 is 4 ohms, the s18 is 8. Other than that the specs are almost identical. Any difference? Is one any better? Same price.